Retrieving Metric Data

Using the metric retrieval methods you can retrieve performance metrics at the cluster, node, and table levels.

Additionally, you have the ability to use existing metric data to create a forecast of future data points for a specific metric. More information on forecasting is available here

Metric Retrieval Methods URL
Retrieve cluster-wide metrics. GET /{cluster_id}/cluster-metrics/{dc}/{metric}
Retrieve cluster-wide metrics about a device. GET /{cluster_id}/cluster-metrics/{dc}/{metric}/{device}
Retrieve cluster-wide metrics about a table. GET /{cluster_id}/cluster-metrics/{dc}/{ks_name}/{cf_name}/{metric}
Retrieve metrics about a node. GET /{cluster_id}/metrics/{node_ip}/{metric}
Retrieve node-specific metrics about a device. GET /{cluster_id}/metrics/{node_ip}/{metric}/{device}
Retrieve node-specific metrics about a table. GET /{cluster_id}/metrics/{node_ip}/{ks_name}/{cf_name}/{metric}
Retrieve a forecast for a cluster-wide metric. GET /{cluster_id}/cluster-metrics/{dc}/{metric}
New way to retrieve all types of metrics. GET /{cluster_id}/new-metrics

You can choose from a large number of metric keys to pass with these methods, making retrieval of a wide spectrum of performance information possible.

Controlling the Metric Data Output

You can also use the following query parameters with these methods to control the output:

Query Parameter Description
start (optional) A timestamp in seconds indicating the beginning of the time range to fetch. When omitted, this defaults to one day before the end parameter.
end (optional) A timestamp in seconds indicating the end of the time range to fetch. When omitted, this defaults to the current time.
step (optional) The resolution of the data points for the metric. Valid input options are: 1, 5, 120, or 1440 minutes; corresponding output intervals are 60, 300, 7200, or 86400 seconds. The default is a 1 minute step.
step (optional; new-metrics API) The new metrics api requires that the step argument be specified in seconds rather than minutes. This is to stay consistent with the return format of the new api. Valid inputs in this case are: 60, 300, 7200, and 86400.
function (optional) The type of aggregation to perform on the metric: min, max, or average. By default, results are returned for all three types of aggregation.
forecast (optional) A boolean flag indicating that we would like to generate a forecast for the time range and step specified. This will use past data to calculate projected data points in the time range specified.

Results of calls to retrieve metrics are returned in the following format:

{
  [<node_ip>: | <device>: | <keyspace.columnfamily>:]
    {
      <function>:
        [
          [<timestamp> <value>],
          ...
        ]
    }
}

By default, the output is metric data points at 60-second intervals over a 24-hour period. Data points are listed in chronological order, starting with the oldest data point first.

GET /{cluster_id}/cluster-metrics/{dc}/{metric}

Aggregate a metric across multiple nodes in the cluster rather than retrieving data about a single node.

Path arguments:
  • cluster_id – A Cluster Config ID.
  • dc – The name of the data center for the nodes. Use the name all to aggregate a metric across all data centers.
  • metric – One of the Cluster Metrics Keys.
Query params:

parameters – The parameters listed in Controlling the Metric Data Output.

Returns metric data across multiple nodes in a cluster.

Example

Get the average write requests per second over to the cluster over all data centers on May 1, 2012 from 8 AM to 5 PM GMT. Show data points at 2-hour (120-minute) intervals.

Using curl’s -G flag to build an HTTP GET request:

curl -G
  http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/write-ops
    -d 'step=120'
    -d 'start=1335859200'
    -d 'end=1335891600'
    -d 'function=average'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/write-ops?step=120&start=1335859200&end=1335891600&function=average'

Output:

Data points at 2-hour (7200 seconds) intervals show the number of write requests per second during business hours on May 1.

{
  "Total": {
    "AVERAGE": [
      [
        1335859200,
        null
      ],
      [
        1335866400,
        13.376885890960693
      ],
      [
        1335873600,
        13.372154712677002
      ],
      [
        1335880800,
        13.365732669830322
      ],
      [
        1335888000,
        13.392115592956543
      ]
    ]
  }
}
GET /{cluster_id}/cluster-metrics/{dc}/{metric}/{device}

Aggregate a disk or network metric, which pertains to a specific device, across multiple nodes in the cluster rather than retrieving data about a single node.

Path arguments:
  • cluster_id – A Cluster Config ID.
  • dc – The name of the data center for the nodes. Use the name all to aggregate a metric across all data centers.
  • metric – One of the Cluster Metrics Keys or Operating System Metrics Keys.
  • device – The device to be measured, which the Node object lists. Use the name all to measure all devices, For example, when requesting a disk metric, all will aggregate metrics from all disk devices.
Query params:

parameters – The parameters listed in Controlling the Metric Data Output.

Examples of Device Arguments

To determine the set of network interfaces that metrics are available for, you can run a query similar to the following:

curl http://localhost:8888/Test_Cluster/nodes/192.168.1.1/network_interfaces

["lo0", "eth0", "eth1"]

In this case, lo0, eth0, and eth1 can all be used.

Disk devices can be discovered in a similar way.

curl http://localhost:8888/Test_Cluster/nodes/192.168.1.1/devices

{
  "commitlog": "sdb",
  "data": ["sda"],
  "saved_caches": "sda",
  "other": ["sdc"]
}

In this case, any of sda, sdb, or sdc may be used.

Finally, metrics are also captured for disk partitions and filesystems:

curl http://localhost:8888/Test_Cluster/nodes/192.168.1.1/partitions

{
  "commitlog": "/dev/sdb1",
  "data": ["/dev/sda1"],
  "saved_caches": "/dev/sda1",
  "other": ["/dev/sdc1"]
}

Here, the available partitions are /dev/sda1, /dev/sdb1, and /dev/sdc1. Keep in mind that you will need to URL-encode the items, so /dev/sda1 will become %2Fdev%2Fsda1.

Using a partition, network interface, or other device name for the device argument returns disk or network metric data about a specific device across multiple nodes. Using all for the device name returns a dictionary of keys (device names) and the values (results for that device).

Example

Get the average GB of space on all disks in all data centers used each day by the cluster from April 11, 2012 00:00:00 to April 26, 2012 00:00:00 GMT.

Using curl’s -G flag to build an HTTP GET request:

curl -G
  http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/os-disk-used/all
    -d 'step=1440'
    -d 'start=1334102400'
    -d 'end=1335398400'
    -d 'function=average'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/os-disk-used/all?step=1440&start=1334102400&end=1335398400&function=average'

Output:

{
  "Total": {
    "AVERAGE": [
      [
        1334102400,
        null
      ],
      [
        1334188800,
        21.000694274902344
      ],
      [
        1334275200,
        8.736943244934082
      ],
      [
        1334361600,
        9.0
      ],
      [
        1334448000,
        19.0
      ],
      [
        1334534400,
        19.0
      ],
      [
        1334620800,
        19.0
      ],
      [
        1334707200,
        19.0
      ],
      [
        1334793600,
        18.629029273986816
      ],
      [
        1334880000,
        19.923184394836426
      ],
      [
        1334966400,
        25.0
      ],
      [
        1335052800,
        25.0
      ],
      [
        1335139200,
        25.923053741455078
      ],
      [
        1335225600,
        26.0
      ],
      [
        1335312000,
        26.549484252929688
      ]
    ]
  }
}
GET /{cluster_id}/cluster-metrics/{dc}/{ks_name}/{cf_name}/{metric}

Aggregate a table metric across multiple nodes in the cluster rather than retrieving data about a single node.

Path arguments:
  • cluster_id – A Cluster Config ID.
  • dc – The name of the data center for the nodes. Use the name all to aggregate a metric across all data centers.
  • ks_name – The keyspace that contains the table to be measured.
  • cf_name – The table to be measured.
  • metric – One of the Table Metrics Keys.
Query params:

parameters – The parameters listed in Controlling the Metric Data Output.

Returns metric data for multiple nodes.

Example

Get the maximum bytes of disk space used for live data by the Users table in the Keyspace1 keyspace of the cluster over all data centers from May 1, 2012 00:00:00 to May 5, 2012 00:00:00 GMT:

Using curl’s -G flag to build an HTTP GET request:

curl -G
  http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/Keyspace1/Users/cf-live-disk-used
  -d 'function=max'
  -d 'start=1335830400'
  -d 'end=1336176000'
  -d 'step=1440'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/Keyspace1/Users/cf-live-disk-used?function=max&start=1335830400&end=1336176000&step=1440'

Output:

Data points at 24-hour intervals show the metrics for the period.

{

  "Total": {
    "MAX": [
      [
        1335830400,
        9740462592.0
      ],
      [
        1335916800,
        9932527616.0
      ],
      [
        1336003200,
        null
      ],
      [
        1336089600,
        10644448512.0
      ]
    ]
  }
}
GET /{cluster_id}/metrics/{node_ip}/{metric}

Retrieve metric data for a single node.

Path arguments:
Query params:

parameters – The parameters listed in Controlling the Metric Data Output.

Returns metric data for a single node.

Example

Get the daily average data load on cluster node 10.11.12.150 from April 20, 2012 00:00:00 to April 26, 2012 00:00:00 GMT:

Using curl’s -G flag to build an HTTP GET request:

curl -G
http://127.0.0.1:8888/Test_Cluster/metrics/10.11.12.150/data-load
  -d 'step=1440'
  -d 'start=1334880000'
  -d 'end=1335398400'
  -d 'function=average'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/metrics/10.11.12.150/data-load?step=1440&start=1334880000&end=1335398400&function=average'

Output:

{
  "10.11.12.150": {
    "AVERAGE": [
      [
        1334880000,
        null
      ],
      [
        1334966400,
        6353770496.0
      ],
      [
        1335052800,
        6560092672.0
      ],
      [
        1335139200,
        6019291136.0
      ],
      [
        1335225600,
        6149050880.0
      ],
      [
        1335312000,
        6271239680.0
      ]
    ]
  }
}
GET /{cluster_id}/metrics/{node_ip}/{metric}/{device}

Aggregate a disk or network metric for a single node.

Path arguments:
Query params:

parameters – The parameters listed in Controlling the Metric Data Output.

Returns disk or network metrics data for a single node.

Example

Get the maximum GB of disk space for all disks used by cluster node 10.11.12.150 from April 30, 2012 at 22:05 to May 1, 2012 8:00:00 GMT:

Using curl’s -G flag to build an HTTP GET request:

curl -G
http://127.0.0.1:8888/Test_Cluster/metrics/10.11.12.150/os-disk-used/all
  -d 'start=1335823500'
  -d 'end=1335859200'
  -d 'step=120'
  -d 'function=max'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/metrics/10.11.12.150/os-disk-used/all?start=1335823500&end=1335859200&step=120&function=max'

Output:

Data points at 2-minute intervals show the disk space used by device /dev/sda1.

{
  "/dev/sda1": {
    "MAX": [
      [
        1335823200,
        null
      ],
      [
        1335830400,
        17.0
      ],
      [
        1335837600,
        16.0
      ],
      [
        1335844800,
        17.0
      ],
      [
        1335852000,
        16.0
      ]
    ]
  }
}
GET /{cluster_id}/metrics/{node_ip}/{ks_name}/{cf_name}/{metric}

Retrieve metric data about a table on a single node.

Path arguments:
  • cluster_id – A Cluster Config ID.
  • node_ip – IP address of the target Node.
  • ks_name – The keyspace that contains the table to be measured.
  • cf_name – The table to be measured.
  • metric – One of the Table Metrics Keys.
Query params:

parameters – The parameters listed in Controlling the Metric Data Output.

Example

Get the daily, maximum response time (in microseconds) to write requests on the Users table in the Keyspace1 keyspace by cluster node 10.11.12.150 from May 1, 2012 at 00:00:00 to May 5, 2012 00:00:00 GMT.

Using curl’s -G flag to build an HTTP GET request:

curl -G
http://127.0.0.1:8888/Test_Cluster/metrics/10.11.12.150/Keyspace1/Users/cf-write-latency-op
  -d 'function=max'
  -d 'start=1335830400'
  -d 'end=1336176000'
  -d 'step=1440'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/metrics/10.11.12.150/Keyspace1/Users/cf-write-latency-op?function=max&start=1335830400&end=1336176000&step=1440'

Output:

{
  "OpsCenter.rollups60": {
    "MAX": [
      [
        1335830400,
        102.28681945800781
      ],
      [
        1335916800,
        124.86614227294922
      ],
      [
        1336003200,
        null
      ],
      [
        1336089600,
        127.14733123779297
      ]
    ]
  }
}
GET /{cluster_id}/cluster-metrics/{dc}/{metric}

Generate a forecast for a metric aggregated across the cluster

Path arguments:
  • cluster_id – A Cluster Config ID.
  • dc – The name of the data center for the nodes. Use the name all to aggregate a metric across all data centers.
  • metric – One of the Cluster Metrics Keys.
Query params:

parameters – The parameters listed in Controlling the Metric Data Output.

Example

Forecast the average write requests per second over for the cluster over all data centers starting from the current time to 4 weeks in the future. Show data points at 1 day (1440-minute) intervals.

Using curl’s -G flag to build an HTTP GET request:

curl -G
  http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/write-ops
    -d "step=1440"
    -d "start=`date +'%s'`"
    -d "end=`date -v+4w +'%s'`"
    -d "forecast=1"

Manually building an HTTP GET request:

curl "http://127.0.0.1:8888/Test_Cluster/cluster-metrics/all/write-ops?step=1440&start=`date +'%s'`&end=`date -v+4w +'%s'`&forecast=1"

Output:

Data points at 1 day (86400 seconds) intervals show the forecasted number of write requests per day for the next 4 weeks. The results will include the data used to generate the forecast. In this example the forecast is based on 12 weeks of data, so the results begin 12 weeks in the past.

{
    "Total": {
        "AVERAGE": [
            [
                1376006400,
                172.18471918718131
            ],
            [
                1376092800,
                182.06741811718813
            ],
            [
                1376179200,
                159.14967219176917
            ],
            ...
            [
                1385769600,
                202.93040370941162
            ],
            [
                1385856000,
                202.78100836277008
            ],
            [
                1385942400,
                202.59301888942719
            ]
        ]
}
GET /{cluster_id}/new-metrics

Retrieve metric data for a single node.

Path arguments:

cluster_id – A Cluster Config ID.
Query params:
  • nodes – A comma separated list of nodes to fetch data for. Either this or node_group must be specified.
  • node_group – A convenient way of specifying a group of nodes to retrieve data for. Can be ‘*’ for all nodes, or the name of a datacenter for the nodes in that datacenter. Either this or nodes must be specified.
  • metrics – A comma separated list of the Metrics Attribute Key Lists to fetch data for. When fetching multiple metrics, all metrics will be fetched using the same nodes, start, end, etc parameters.
  • columnfamilies – A comma separated list of ‘<keyspace>.columnfamily’ strings indicating the tables to fetch the given metrics for. Required when fetching metrics that are specific to a certain table.
  • tiers – A comma separated list of storage tier numbers indicating the tiers to fetch the given metrics for. Required when fetching metrics are specific to a certain storage tier
  • devices – A comma separated list of device strings indicating the devices to fetch the given metrics for. Required when fetching metrics that are specific to a certain disk or network device.
  • node_aggregation – Indicates whether or not to aggregate the results across nodes. A ‘0’ value indicates false and a ‘1’ value indicates true.
  • parameters (additional) – The parameters listed in Controlling the Metric Data Output.

Returns metric data.

Examples

Get the daily average data load on cluster nodes 10.11.12.150, 10.11.12.151 from April 20, 2012 00:00:00 to April 26, 2012 00:00:00 GMT:

Using curl’s -G flag to build an HTTP GET request:

curl -G
http://127.0.0.1:8888/Test_Cluster/new-metrics
  -d 'metrics=data-load'
  -d 'nodes=10.11.12.150,10.11.12.151'
  -d 'step=86400'
  -d 'start=1334880000'
  -d 'end=1335398400'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/new-metrics?metrics=data-load&nodes=10.11.12.150,10.11.12.151&step=86400&start=1334880000&end=1335398400'

Output:

{
  "metrics": ["data-load"],
  "bounds": {"start": 1334880000, "end": 1335312000, "step": 86400},
  "aggregation_function": null,
  "nodes": ["10.11.12.150", "10.11.12.151"],
  "data": {
    "10.11.12.150": [
      {"metric": "data-load",
       "data-points":
          [
              [4353770496.0, 4353770496.0, 4353770496.0],
              [6353770496.0, 6353770496.0, 6353770496.0],
              [6560092672.0, 6560092672.0, 6560092672.0],
              [6019291136.0, 6019291136.0, 6019291136.0],
              [6149050880.0, 6149050880.0, 6149050880.0],
              [6271239680.0, 6271239680.0, 6271239680.0]
          ]
      }
    ],
    "10.11.12.151": [
      {"metric": "data-load",
       "data-points":
          [
              [4353770496.0, 4353770496.0, 4353770496.0],
              [6353770496.0, 6353770496.0, 6353770496.0],
              [6560092672.0, 6560092672.0, 6560092672.0],
              [6019291136.0, 6019291136.0, 6019291136.0],
              [6149050880.0, 6149050880.0, 6149050880.0],
              [6271239680.0, 6271239680.0, 6271239680.0]
          ]
      }
    ]
  }
}

Get the cluster average for data load and write ops from April 20, 2012 00:00:00 to April 2, 2012 00:00:00 GMT:

Using curl’s -G flag to build an HTTP GET request:

curl -G
http://127.0.0.1:8888/Test_Cluster/new-metrics
  -d 'metrics=data-load,write-latency-op'
  -d 'node_group=*'
  -d 'step=86400'
  -d 'start=1334880000'
  -d 'end=1335398400'
  -d 'node_aggregation=1'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/new-metrics?metrics=data-load,write-latency-op&node_group=*&step=86400&start=1334880000&end=1335398400&node_aggregation=1'

Output:

{
  "metrics": ["data-load", "write-latency-op"],
  "bounds": {"start": 1334880000, "end": 1335312000, "step": 86400},
  "aggregation_function": {
    "data-load": "sum",
    "write-latency-op": "average"
  }
  "nodes": ["10..11.12.150", "10.11.12.151"],
  "data": {
    "aggregate": [
      {"metric": "data-load",
       "data-points":
          [
              [4353770496.0, 4353770496.0, 4353770496.0],
              [6353770496.0, 6353770496.0, 6353770496.0],
              [6560092672.0, 6560092672.0, 6560092672.0],
              [6019291136.0, 6019291136.0, 6019291136.0],
              [6149050880.0, 6149050880.0, 6149050880.0],
              [6271239680.0, 6271239680.0, 6271239680.0]
          ]
      },
      {"metric": "write-latency-op",
       "data-points":
          [
              [4353770496.0, 4353770496.0, 4353770496.0],
              [6353770496.0, 6353770496.0, 6353770496.0],
              [6560092672.0, 6560092672.0, 6560092672.0],
              [6019291136.0, 6019291136.0, 6019291136.0],
              [6149050880.0, 6149050880.0, 6149050880.0],
              [6271239680.0, 6271239680.0, 6271239680.0]
          ]
      },
    ]
  }
}

Get the write-ops for multipe cfs for all nodes from April 20, 2012 00:00:00 to April 2, 2012 00:00:00 GMT:

Using curl’s -G flag to build an HTTP GET request:

curl -G
http://127.0.0.1:8888/Test_Cluster/new-metrics
  -d 'metrics=cf-write-ops'
  -d 'node_group=*'
  -d 'columnfamilies=OpsCenter.events,OpsCenter.settings'
  -d 'step=86400'
  -d 'start=1334880000'
  -d 'end=1335398400'

Manually building an HTTP GET request:

curl 'http://127.0.0.1:8888/Test_Cluster/new-metrics?metrics=cf-write-ops&node_group=*&columnfamilies=OpsCenter.events,OpsCenter.settings&step=86400&start=1334880000&end=1335398400'

Output:

{
  "metrics": ['cf-write-ops'],
  "bounds": {"start": 1334880000, "end": 1335312000, "step": 86400},
  "aggregation_function": null
  "nodes": ["10.11.12.150", "10.11.12.151"],
  "columnfamilies": ["OpsCenter.events", "OpsCenter.settings"],
  "data": {
    "10.11.12.150": [
      {"metric": "cf-write-ops",
       "columnfamily": "OpsCenter.events",
       "data-points":
          [
              [4353770496.0, 4353770496.0, 4353770496.0],
              [6353770496.0, 6353770496.0, 6353770496.0],
              [6560092672.0, 6560092672.0, 6560092672.0],
              [6019291136.0, 6019291136.0, 6019291136.0],
              [6149050880.0, 6149050880.0, 6149050880.0],
              [6271239680.0, 6271239680.0, 6271239680.0]
          ]
      },
    ],
    "10.11.12.151": [
      {"metric": "cf-write-ops",
       "columnfamily": "OpsCenter.settings",
       "data-points":
          [
              [4353770496.0, 4353770496.0, 4353770496.0],
              [6353770496.0, 6353770496.0, 6353770496.0],
              [6560092672.0, 6560092672.0, 6560092672.0],
              [6019291136.0, 6019291136.0, 6019291136.0],
              [6149050880.0, 6149050880.0, 6149050880.0],
              [6271239680.0, 6271239680.0, 6271239680.0]
          ]
      },
    ]
  }
}

Metrics Attribute Key Lists

This section contains these tables of metric keys to use with resources that retrieve OpsCenter performance data:

Cluster Metrics Keys

This list of keys corresponds to database metrics collected by OpsCenter:

Key Units Description
write-ops /sec The number of write requests per second on the coordinator nodes, analogous to client writes. Monitoring the number of requests over a given time period reveals system write workload and usage patterns.
write-histogram ms/op The min, median, max, 90th, and 99th percentiles of a client writes. The time period starts when a node receives a client write request, and ends when the node responds back to the client. Depending on consistency level and replication factor, this may include the network latency from writing to the replicas.
write-failures /sec The number of write requests on the coordinator nodes that fail due to errors returned from replicas.
write-timeouts /sec The number of server write timeouts per second on the coordinator nodes.
write-unavailables /sec The number of write requests per second on the coordinator nodes, that fail because not enough replicas are available.
read-ops /sec The number of read requests per second on the coordinator nodes, analogous to client reads. Monitoring the number of requests over a given time period reveals system read workload and usage patterns.
read-histogram ms/op The min, median, max, 90th, and 99th percentiles of a client reads. The time period starts when a node receives a client read request, and ends when the node responds back to the client. Depending on consistency level and replication factor, this may include the network latency from requesting the data’s replicas.
read-failures /sec The number of read requests on the coordinator nodes that fail due to errors returned from replicas.
read-timeouts /sec The number of server read timeouts per second on the coordinator nodes.
read-unavailables /sec The number of read requests per second on the coordinator nodes, that fail because not enough replicas are available.
nonheap-committed – Allocated memory, guaranteed for Java nonheap.
nonheap-max – Maximum amount that the Java nonheap can grow.
nonheap-used – Average amount of Java nonheap memory used.
heap-committed – Allocated memory guaranteed for the Java heap.
heap-max – Maximum amount that the Java heap can grow.
heap-used – Average amount of Java heap memory used.
cms-collection-count /sec Number of concurrent mark sweep garbage collections performed per second.
par-new-collection-count /sec Number of ParNew garbage collections performed per second. ParNew collections pause all work in the JVM but should finish quickly.
cms-collection-time ms/sec Average number of milliseconds spent performing CMS garbage collections per second.
par-new-collection-time ms/sec Average number of milliseconds spent performing ParNew garbage collections per second. ParNew collections pause all work in the JVM but should finish quickly.
g1-old-collection-count /sec Number of G1 old generation garbage collections performed per second.
g1-old-collection-time ms/sec Average number of milliseconds spent performing G1 old generation garbage collections per second.
g1-young-collection-count /sec Number of G1 young generation garbage collections performed per second.
g1-young-collection-time ms/sec Average number of milliseconds spent performing G1 young generation garbage collections per second.
data-load – The live disk space used by all tables on a node.
total-bytes-compacted /sec Number of bytes compacted per second.
actual-total-compactions-completed /sec Number of compaction tasks completed per second.
total-compactions-completed /sec Number of sstable scans per second that could result in a compaction.
pending-compaction-tasks – Estimated number of compactions required to achieve the desired state. This includes the pending queue to the compaction executor and additional tasks that may be created from their completion.
dropped-counter-mutations drops/sec Mutation was seen after the timeout (write_request_timeout_in_ms) so was thrown away. This client might have timed out before it met the required consistency level, but might have succeeded as well. Hinted handoffs and read repairs should resolve inconsistencies but a repair can ensure it.
dropped-mutations drops/sec Mutation was seen after the timeout (write_request_timeout_in_ms) so was thrown away. This client might have timed out before it met the required consistency level, but might have succeeded as well. Hinted handoffs and read repairs should resolve inconsistencies but a repair can ensure it.
dropped-reads drops/sec A local read request was received after the timeout (read_request_timeout_in_ms) so it was thrown away because it would have already either been completed and sent to client or sent back as a timeout error.
dropped-ranged-slice-reads drops/sec A local ranged read request was received after the timeout (range_request_timeout_in_ms) so it was thrown away because it would have already either been completed and sent to client or sent back as a timeout error.
dropped-read-repairs drops/sec The Mutation was seen after the timeout (write_request_timeout_in_ms) so was thrown away. With the read repair timeout, the node still exists in an inconsistent state.
key-cache-hits /sec The number of key cache hits per second. This will avoid possible disk seeks when finding a partition in an SSTable. This metric only applies to SSTables created by DSE versions earlier than 6.0.
key-cache-requests /sec The number of key cache requests per second. This metric only applies to SSTables created by DSE versions earlier than 6.0.
key-cache-hit-rate – The percentage of key cache lookups that resulted in a hit. This metric only applies to SSTables created by DSE versions earlier than 6.0.
row-cache-hits /sec The number of row cache hits per second.
row-cache-requests /sec The number of row cache requests per second.
row-cache-hit-rate – The percentage of row cache lookups that resulted in a hit.
native-connections – The number of clients connected using the native protocol.
read-repair-attempted /sec Number of read requests where the number of nodes queried possibly exceeds the consistency level requested in order to check for a possible digest mismatch.
read-repaired-background /sec Corresponds to a digest mismatch that occurred after a completed read, outside of the client read loop.
read-repaired-blocking /sec Corresponds to the number of times there was a digest mismatch within the requested consistency level and a full data read was started.
speculative-retries retries Number of speculative retries for all column families.
stream-out-total /sec Data streamed out from this node to all other nodes, for all tables.
stream-in-total /sec Data streams in to this node from all other nodes, for all tables.
hint-creation-rate /sec Rate at which new individual hints are stored on this node, to be replayed to peers.
in-memory-percent-used – The percentage of memory allocated for in-memory tables currently in use.
view-write-histogram ms/op The min, median, max, 90th, and 99th percentiles of the time from when base mutation is applied to memtable until CL.ONE is achieved on the async write to the tables materialized views. An estimate to determine the lag between base table mutations and the views consistency.
view-replicas-success mutations Number of view mutations sent to replicas that have been acknowledged.
view-replicas-pending mutations Number of view mutations sent to replicas where the replicas acknowledgement hasn’t been received.
cells-scanned-during-read cells The min, median, max, 90th, and 99th percentile of how many cells were scanned during a read.
pending-graph-query-threads – Number of pending tasks in the GraphQueryThreads thread pool.
active-graph-query-threads – Number of active tasks in the GraphQueryThreads thread pool.
completed-graph-query-threads – Number of tasks completed by the GraphQueryThreads thread pool.
pending-graph-scheduled-threads – Number of pending tasks in the GraphScheduledThreads thread pool.
active-graph-scheduled-threads – Number of active tasks in the GraphScheduledThreads thread pool.
completed-graph-scheduled-threads – Number of tasks completed by the GraphScheduledThreads thread pool.
pending-graph-system-threads – Number of pending tasks in the GraphSystemThreads thread pool.
active-graph-system-threads – Number of active tasks in the GraphSystemThreads thread pool.
completed-graph-system-threads – Number of tasks completed by the GraphSystemThreads thread pool.
pending-gremlin-worker-threads – Number of pending tasks in the GremlinWorkerThreads thread pool.
active-gremlin-worker-threads – Number of active tasks in the GremlinWorkerThreads thread pool.
completed-gremlin-worker-threads – Number of tasks completed by the GremlinWorkerThreads thread pool.
percentage-repaired % Percentage of data (uncompressed) marked as repaired across all non-system tables on a node. Tables with a replication factor of 1 are excluded.
read-coordinator-nonreplica /sec Rate of coordinated reads to a node where that node is not a replica for that partition.
read-coordinator-preferother /sec Rate of coordinated reads to a node where that node did not choose itself as a replica for the read request.
hints-on-disk – The number of hints currently stored on disk, to be replayed to peers.
hint-replay-success-rate /sec Rate of successful individual hint replays to peers. If one or more individual hints fail to replay in a batch, the successful hints in that batch will be replayed again and double counted in this metric.
hint-replay-error-rate /sec Rate of failed individual hint replays. Replay of a single hint can fail more than once if retried.
hint-replay-timeout-rate /sec Rate of timed out individual hint replays. Replay of a single hint can timeout more than once if retried.
hint-replay-received-rate /sec Rate of successful individual hints replayed to this node, from other peers.
cross-node-latency ms/op The min, median, max, 90th, and 99th percentiles of the latency of messages between nodes. The time period starts when a node sends a message and ends when the current node receives it.
nodesync-data-repaired bytes Bytes of data that were inconsistent and needed synchronization.
nodesync-data-validated bytes Bytes of data checked for consistency.
nodesync-repair-data-sent bytes Total bytes of data transferred between all nodes during synchronization.
nodesync-objects-repaired objects Number of rows and range tombstones that were inconsistent and needed synchronization.
nodesync-objects-validated objects Number of rows and range tombstones checked for consistency.
nodesync-repair-objects-sent objects Total number of rows and range tombstones transferred between all nodes during synchronization.
nodesync-processed-pages pages Number of pages (internal groupings of data) processed.
nodesync-full-in-sync-pages pages Number of processed pages that were not in need of synchronization.
nodesync-full-repaired-pages pages Number of processed pages that were in need of synchronization.
nodesync-partial-in-sync-pages pages Number of in sync pages for which a response was gotten from only a partial number of replicas.
nodesync-partial-repaired-pages pages Number of repaired pages for which a response was gotten from only a partial number of replicas.
nodesync-uncompleted-pages pages Number of processed pages not having enough responses to perform synchronization.
nodesync-failed-pages pages Number of processed pages for which an unknown error prevented proper synchronization completion.
dropped-view-mutations drops/sec Mutation of Materialized View was seen after the timeout (write_request_timeout_in_ms) so was thrown away. This client might have timed out before it met the required consistency level, but might have succeeded as well. Hinted handoffs and read repairs should resolve inconsistencies but a repair can ensure it.
dropped-lwt drops/sec Lightweight Transaction was seen after the timeout (write_request_timeout_in_ms) so was thrown away. This client might have timed out before it met the required consistency level, but might have succeeded as well. Hinted handoffs and read repairs should resolve inconsistencies but a repair can ensure it.
dropped-hints drops/sec Hinted Handoff was seen after the timeout (write_request_timeout_in_ms) so was thrown away. Repairing the data or using NodeSync, should resolve data inconsistencies.
dropped-truncates drops/sec Truncate operation was seen after the timeout (truncate_request_timeout_in_ms) so was thrown away.
dropped-snapshots drops/sec Snapshot Request was seen after the timeout (request_timeout_in_ms) so was thrown away. Snapshot should be retried.
dropped-schemas drops/sec Schema change was seen after the timeout (request_timeout_in_ms) so was thrown away. Schema agreement may not have been reached immediately, but this will eventually resolve itself.
dropped-repairs drops/sec Repair message was seen after the timeout so was thrown away.
dropped-other drops/sec Miscellaneous message was seen after the timeout so was thrown away.
dropped-node-sync drops/sec Node-sync message was seen after the timeout so was thrown away.
dropped-batch-store drops/sec Batch store message was seen after the timeout so was thrown away.

Thread Pool Metrics Keys

This list of keys corresponds to thread pool metrics collected by OpsCenter:

Key Description
pending-flushes Number of memtables queued for the flush process. A flush sorts and writes the memtables to disk.
pending-gossip-stage Number of gossip messages and acknowledgments queued and waiting to be sent or received.
pending-internal-response-stage Number of pending tasks from internal tasks, such as nodes joining and leaving the cluster.
pending-anti-entropy-stage Repair tasks pending, such as handling the merkle tree transfer after the validation compaction.
pending-cache-cleanup-stage Tasks pending to clean row caches during a cleanup compaction.
pending-memtable-post-flush Tasks related to the last step in flushing memtables to disk as SSTables. Includes removing unnecessary commitlog files and committing Solr-based secondary indexes.
pending-migration-stage Number of pending tasks from system methods that modified the schema.
pending-misc-stage Number of pending tasks from infrequently run operations, such as taking a snapshot or processing the notification of a completed replication.
pending-read-stage Number of pending read requests. Read requests read data off of disk and deserialize cached data.
pending-read-repair-stage Number of read repair operations in the queue waiting to run.
pending-request-response-stage Number of pending callbacks to execute after a task on a remote node completes.
pending-mutation-stage Number of write requests received by the cluster and waiting to be handled.
pending-validation-executor Pending task to read data from sstables and generate a merkle tree for a repair.
pending-compaction-executor Pending compactions that are known. This may deviate from “pending compactions” which includes an estimate of tasks that these pending tasks may create after completion.
pending-pending-range-calculator Pending tasks to calculate the ranges according to bootsrapping and leaving nodes.
active-flushes Up to memtable_flush_writers concurrent tasks to flush and write the memtables to disk.
active-gossip-stage Number of gossip messages and acknowledgments actively being sent or received.
active-internal-response-stage Number of active tasks from internal tasks, such as nodes joining and leaving the cluster.
active-anti-entropy-stage Repair tasks active, such as handling the merkle tree transfer after the validation compaction.
active-cache-cleanup-stage Tasks to clean row caches during a cleanup compaction.
active-memtable-post-flush Tasks related to the last step in flushing memtables to disk as SSTables. Includes removing unnecessary commitlog files and committing Solr-based secondary indexes.
active-migration-stage Number of active tasks from system methods that modified the schema.
active-misc-stage Number of active tasks from infrequently run operations, such as taking a snapshot or processing the notification of a completed replication.
active-read-stage Number of active read requests. Read requests read data off of disk and deserialize cached data.
active-read-repair-stage Number of read repair operations actively being run.
active-request-response-stage Number of callbacks to being executed after a task on a remote node is completed.
active-mutation-stage Number of write requests being handled.
active-validation-executor Active task to read data from sstables and generate a merkle tree for a repair.
active-compaction-executor Active compactions that are known.
active-pending-range-calculator Active tasks to calculate the ranges according to bootsrapping and leaving nodes.
completed-flushes Number of memtables flushed to disk since the nodes start.
completed-gossip-stage Number of gossip messages and acknowledgments recently sent or received.
completed-internal-response-stage Number of recently completed tasks from internal tasks, such as nodes joining and leaving the cluster.
completed-anti-entropy-stage Repair tasks recently completed, such as handling the merkle tree transfer after the validation compaction.
completed-cache-cleanup-stage Tasks to clean row caches during a cleanup compaction.
completed-memtable-post-flush Tasks related to the last step in flushing memtables to disk as SSTables. Includes removing unnecessary commitlog files and committing Solr-based secondary indexes.
completed-migration-stage Number of completed tasks from system methods that modified the schema.
completed-misc-stage Number of completed tasks from infrequently run operations, such as taking a snapshot or processing the notification of a completed replication.
completed-read-stage Number of completed read requests. Read requests read data off of disk and deserialize cached data.
completed-read-repair-stage Number of read repair operations recently completed.
completed-request-response-stage Number of completed callbacks executed after a task on a remote node is completed.
completed-mutation-stage Number of write requests received by the cluster that have been handled.
completed-validation-executor Completed tasks to read data from sstables and generate a merkle tree for a repair.
completed-compaction-executor Completed compactions.
completed-pending-range-calculator Completed tasks to calculate the ranges according to bootsrapping and leaving nodes.
pending-counter-mutations Pending tasks to execute local counter mutations.
active-counter-mutations Up to concurrent_counter_writes running tasks that execute local counter mutations.
completed-counter-mutations Number of local counter mutations that have been executed.
memtable-reclaim-pending Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.
memtable-reclaim-active Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.
completed-memtable-reclaim Waits for current reads to complete and then frees the memory formerly used by the obsoleted memtables.
pending-view-mutation-stage Number of mutations to apply locally after modifications to a base table.
active-view-mutation-stage Number of mutations to being applied locally after modifications to a base table.
completed-view-mutation-stage Number of mutations applied locally after modifications to a base table.
pending-hint-dispatcher Pending tasks to send the stored hinted handoffs to a host.
active-hint-dispatcher Up to max_hints_delivery_threads tasks, each dispatching all hinted handoffs to a host.
completed-hint-dispatcher Number of tasks to transfer hints to a host that have completed.
pending-secondary-index-management Any initialization work when a new index instance is created. This may involve costly operations such as (re)building the index.
active-secondary-index-management Any initialization work when a new index instance is created. This may involve costly operations such as (re)building the index.
completed-secondary-index-management Any initialization work when a new index instance is created. This may involve costly operations such as (re)building the index.
active-authentication Authentication Active
completed-authentication Authentication Completed
active-read-range Read Range Active
completed-read-range Read Range Completed
active-execute-statement Execute Statement Active
completed-execute-statement Execute Statement Completed
active-timed-speculate Timed Speculate Active
completed-timed-speculate Timed Speculate Completed
active-unknown Unknown Active
completed-unknown Unknown Completed
active-truncate Truncate Active
completed-truncate Truncate Completed
active-timed-histogram-aggregate Timed Histogram Aggregate Active
completed-timed-histogram-aggregate Timed Histogram Aggregate Completed
active-counter-acquire-lock Counter Acquire Lock Active
completed-counter-acquire-lock Counter Acquire Lock Completed
active-read Read Active
completed-read Read Completed
active-cas CAS Active
completed-cas CAS Completed
active-write-switch-for-memtable Write Switch For Memtable Active
completed-write-switch-for-memtable Write Switch For Memtable Completed
active-read-disk-async Read Disk Async Active
completed-read-disk-async Read Disk Async Completed
active-timed-unknown Timed Unknown Active
completed-timed-unknown Timed Unknown Completed
active-timed-meter-tick Timed Meter Tick Active
completed-timed-meter-tick Timed Meter Tick Completed
active-timed-timeout Timed Timeout Active
completed-timed-timeout Timed Timeout Completed
active-write Write Active
completed-write Write Completed
active-write-defragment Write Defragment Active
completed-write-defragment Write Defragment Completed
active-read-secondary-index Read Secondary Index Active
completed-read-secondary-index Read Secondary Index Completed
pending-read-range Read Range Pending
total-blocked-read Total Read Blocked
total-blocked-read-range Total Read Range Blocked
total-blocked-write-defragment Total Write Defragment Blocked
total-blocked-write Total Write Blocked
pending-write-defragment Write Defragment Pending
pending-write Write Pending
pending-read Read Pending
active-eventloop-spin Eventloop Spin Active
completed-read-deferred Read Deferred Completed
completed-authorization Authorization Completed
completed-batch-replay Batch Replay Completed
active-write-await-commitlog-segment Write Await Commitlog Segment Active
active-eventloop-park Eventloop Park Active
active-read-switch-for-response Read Switch For Response Active
active-nodesync-validation Nodesync Validation Active
active-read-switch-for-iterator Read Switch For Iterator Active
active-batch-remove Batch Remove Active
active-batch-replay Batch Replay Active
active-read-range-switch-for-response Read Range Switch For Response Active
active-write-switch-for-response Write Switch For Response Active
completed-batch-remove Batch Remove Completed
completed-batch-store-response Batch Store Response Completed
active-write-memtable-full Write Memtable Full Active
pending-lwt-propose Lwt Propose Pending
active-write-await-commitlog-sync Write Await Commitlog Sync Active
completed-nodesync-validation Nodesync Validation Completed
completed-lwt-commit Lwt Commit Completed
completed-read-switch-for-response Read Switch For Response Completed
active-eventloop-yield Eventloop Yield Active
active-lwt-prepare Lwt Prepare Active
completed-lwt-propose Lwt Propose Completed
pending-batch-store Batch Store Pending
completed-read-switch-for-iterator Read Switch For Iterator Completed
pending-lwt-prepare Lwt Prepare Pending
completed-write-memtable-full Write Memtable Full Completed
pending-truncate Truncate Pending
pending-read-deferred Read Deferred Pending
completed-eventloop-spin Eventloop Spin Completed
completed-write-switch-for-response Write Switch For Response Completed
completed-eventloop-park Eventloop Park Completed
active-lwt-propose Lwt Propose Active
completed-lwt-prepare Lwt Prepare Completed
active-authorization Authorization Active
completed-eventloop-yield Eventloop Yield Completed
completed-batch-store Batch Store Completed
active-batch-store Batch Store Active
pending-batch-remove Batch Remove Pending
active-lwt-commit Lwt Commit Active
pending-lwt-commit Lwt Commit Pending
completed-write-await-commitlog-segment Write Await Commitlog Segment Completed
completed-read-range-switch-for-response Read Range Switch For Response Completed
active-batch-store-response Batch Store Response Active
completed-write-await-commitlog-sync Write Await Commitlog Sync Completed
active-read-deferred Read Deferred Active
total-blocked-batch-remove Total Batch Remove Blocked
total-blocked-read-deferred Total Read Deferred Blocked
total-blocked-lwt-commit Total Lwt Commit Blocked
total-blocked-lwt-propose Total Lwt Propose Blocked
total-blocked-truncate Total Truncate Blocked
total-blocked-lwt-prepare Total Lwt Prepare Blocked
total-blocked-batch-store Total Batch Store Blocked

Table Metrics Keys

This list of keys corresponds to table-specific metrics collected by OpsCenter:

Key Units Description
cf-write-ops /sec Local write requests per second. Local writes update the table’s memtable and appends to a commitlog.
cf-local-write-latency ms/op The min, median, max, 90th, and 99th percentile of the response times to write data to a table’s memtable. The elapsed time from when the replica receives the request from a coordinator and returns a response.
cf-read-ops /sec Local read requests per second. Local reads retrieve data from a table’s memtable and any necessary SSTables on disk.
cf-local-read-latency ms/op The min, median, max, 90th, and 99th percentile of the response time to read data from the memtable and sstables for a specific table. The elapsed time from when the replica receives the request from a coordinator and returns a response.
cf-live-disk-used – Disk space used by live SSTables. There might be obsolete SSTables not included.
cf-total-disk-used – Disk space used by a table by SSTables, including obsolete ones waiting to be garbage collected.
cf-live-sstables – Total number of SSTables for a table.
cf-sstables-per-read sstables The min, median, max, 90th, and 99th percentile of how many SSTables are accessed during a read. Includes sstables that undergo bloom-filter checks, even if no data is read from the sstable.
cf-partition-size   The min, median, max, 90th, and 99th percentile of the size (in bytes) of partitions of this table.
cf-column-count cells The min, median, max, 90th, and 99th percentile of how many cells exist in partitions for this table.
cf-bf-space-used – The total size of all the SSTables’ bloom filters for this table.
cf-bf-false-positives /sec Number of bloom filter false positives per second.
cf-bf-false-ratio – Percentage of bloom filter lookups that resulted in a false positive.
solr-requests /sec Requests per second made to a specific Solr core/index.
solr-avg-time-per-req ms/request Average time a search query takes in a DSE cluster using DSE Search.
solr-errors /sec Errors per second that occur for a specific Solr core/index.
solr-timeouts /sec Timeouts per second on a specific Solr core/index.
solr-index-size KB Size of the Solr core on disk.
cf-sstable-size – –
cf-speculative-retries retries Number of speculative retries for this table.
cf-bf-offheap – Total off heap memory used by bloom filters from all live SSTables in a table.
cf-index-summary-offheap – Total off heap memory used by the index summary of all live SSTables in a table.
cf-compression-data-offheap – Total off heap memory used by the compression metadata of all live SSTables in a table.
cf-memtable-offheap – Off heap memory used by a table’s current memtable.
cf-all-memtables-heapsize – An estimate of the space used in JVM heap memory for all memtables. This includes ones that are currently being flushed and related secondary indexes.
cf-all-memtables-livedatasize – An estimate of the space used for ‘live data’ (off-heap, excluding overhead) for all memtables. This includes ones that are currently being flushed and related secondary indexes.
cf-all-memtables-offheapsize – An estimate of the space used in off-heap memory for all memtables. This includes ones that are currently being flushed and related secondary indexes.
cf-row-size – Approximate number of partitions. This may be off given duplicates in memtables and sstables are both counted and there is a very small error percentage inherited from the HyperLogLog data structure.
cf-tombstones-per-read tombstones The min, median, max, 90th, and 99th percentile of how many tombstones are read during a read.
cf-write-latency-legacy ms/op <b>Deprecated</b>. Median response time to write data to a table’s memtable. The elapsed time from when the replica receives the request from a coordinator and returns a response.
cf-read-latency-legacy ms/op <b>Deprecated</b>. Median response time to read data from the memtable and SSTables for a specific table. The elapsed time from when the replica receives the request from a coordinator and returns a response.
cf-coordinator-read-latency ms/op The min, median, max, 90th, and 99th percentiles of client reads on this table. The time period starts when a node receives a client read request, and ends when the node responds back to the client. Depending on consistency level and replication factor, this may include the network latency from requesting the data’s replicas.
cf-coordinator-read-ops /sec The number of read requests per second for a particular table on the coordinator nodes. Monitoring the number of requests over a given time period reveals table read workload and usage patterns.
cf-cells-scanned-during-read cells The min, median, max, 90th, and 99th percentile of how many cells were scanned during a read.
cf-tier-size – Disk space used by a table by SSTables for the tier.
cf-tier-sstables sstables Number of SSTables in a tier for a table.
cf-tier-max-data-age – Timestamp in local server time that represents an upper bound to the newest piece of data stored in the SSTable. When a new SSTable is flushed, it is set to the time of creation. When an SSTable is created from compaction, it is set to the max of all merged SSTables.
cf-percentage-repaired % Percentage of data (uncompressed) marked as repired for a given table on a node. This metric is only meaningful for replication factor > 1.
nodesync-tbl-data-repaired bytes Bytes of data that were inconsistent and needed synchronization.
nodesync-tbl-data-validated bytes Bytes of data checked for consistency.
nodesync-tbl-repair-data-sent bytes Total bytes of data transferred between all nodes during synchronization.
nodesync-tbl-objects-repaired objects Number of rows and range tombstones that were inconsistent and needed synchronization.
nodesync-tbl-objects-validated objects Number of rows and range tombstones checked for consistency.
nodesync-tbl-repair-objects-sent objects Total number of rows and range tombstones transferred between all nodes during synchronization.
nodesync-tbl-processed-pages pages Number of pages (internal groupings of data) processed.
nodesync-tbl-full-in-sync-pages pages Number of processed pages that were not in need of synchronization.
nodesync-tbl-full-repaired-pages pages Number of processed pages that were in need of synchronization.
nodesync-tbl-partial-in-sync-pages pages Number of in sync pages for which a response was gotten from only a partial number of replicas.
nodesync-tbl-partial-repaired-pages pages Number of repaired pages for which a response was gotten from only a partial number of replicas.
nodesync-tbl-uncompleted-pages pages Number of processed pages not having enough responses to perform synchronization.
nodesync-tbl-failed-pages pages Number of processed pages for which an unknown error prevented proper synchronization completion.

Storage Tier Metrics Keys

This list of keys corresponds storage tier-specific metrics collected by OpsCenter:

Key Units Description
cf-tier-size – Disk space used by a table by SSTables for the tier.
cf-tier-sstables sstables Number of SSTables in a tier for a table.
cf-tier-max-data-age – Timestamp in local server time that represents an upper bound to the newest piece of data stored in the SSTable. When a new SSTable is flushed, it is set to the time of creation. When an SSTable is created from compaction, it is set to the max of all merged SSTables.

Operating System Metrics Keys

This list of keys corresponds to operating system (OS) metrics collected by OpsCenter:

Key OS Units Description
os-memory linux MB Stacked graph of used, cached, and free memory.
os-memory-osx osx MB Stacked graph of used and free memory.
os-memory-free linux, osx MB Total system memory currently free.
os-memory-used linux, osx MB Total system memory currently used.
os-memory-shared linux MB Total amount of memory in shared memory space.
os-memory-buffers linux MB Total system memory currently buffered.
os-memory-cached linux MB Total system memory currently cached.
os-memory-win windows MB Stacked graph of committed, cached, paged, non-paged, and free memory.
os-memory-avail windows MB Available physical memory.
os-memory-committed windows MB Memory in use by the operating system.
os-memory-pool-paged windows MB Allocated pool-paged-resident memory.
os-memory-pool-nonpaged windows MB Allocated pool-nonpaged memory.
os-memory-sys-cache-resident windows MB Memory used by the file cache.
cpu linux – Stacked graph of iowait, steal, nice, system, user, and idle CPU usage.
cpu-osx osx – Stacked graph of idle, user, and system CPU usage.
cpu-win windows – Stacked graph of user, privileged, and idle CPU usage.
os-cpu-user – – Time the CPU devotes to user processes.
os-cpu-system linux, osx – Time the CPU devotes to system processes.
os-cpu-idle – – Time the CPU is idle.
os-cpu-iowait linux – Time the CPU devotes to waiting for I/O to complete.
os-cpu-steal linux – Time the CPU devotes to tasks stolen by virtual operating systems.
os-cpu-nice linux – Time the CPU devotes to processing nice tasks.
os-cpu-privileged windows – Time the CPU devotes to processing privileged instructions.
os-load – – Operating system load average. One minute value parsed from /proc/loadavg on Linux systems.
os-disk-usage – – Disk space used by Cassandra at a given time.
os-disk-free – GB Free space on a specific disk partition.
os-disk-used – GB Disk space used by Cassandra at a given time.
os-disk-read-throughput linux, windows MB/sec Average disk throughput for read operations.
os-disk-write-throughput linux, windows MB/sec Average disk throughput for write operations.
os-disk-throughput osx MB/sec Average disk throughput for read and write operations.
os-disk-read-rate linux, windows /sec Rate of reads per second to the disk.
os-disk-write-rate linux, windows /sec Rate of writes per second to the disk.
os-disk-await linux, windows ms Average completion time of each request to the disk.
os-disk-request-size linux, osx sectors Average size of read requests issued to the disk.
os-disk-request-size-kb windows KB Average size of read requests issued to the disk.
os-disk-queue-size linux, windows requests Average number of requests queued due to disk latency issues.
os-disk-utilization linux, windows – CPU time consumed by disk I/O.
os-net-received – KB/sec Speed of data received from the network.
os-net-sent – KB/sec Speed of data sent across the network.
os-disk-space – GB –
os-disk-throughput-grouped linux, windows MB/sec –
os-disk-rate linux, windows /sec –
os-net-traffic – KB/sec –
os-net-sent-win – – Speed of data sent across the network.
os-net-received-win – – Speed of data received from the network.