Skip to content

Commit

Permalink
Merge pull request #54 from zegelin/keyspace-metrics
Browse files Browse the repository at this point in the history 
Add support for exporting Cassandra's keyspace- and node-level metrics.
  • Loading branch information
@zegelin
zegelin authored Jan 25, 2020
2 parents a4a290d + 9723977 commit 9911b5d
Show file tree
Hide file tree
Showing 3 changed files with 272 additions and 128 deletions.
67 changes: 43 additions & 24 deletions README.md
View file
Original file line number Diff line number Diff line change
Expand Up @@ -100,28 +100,26 @@ The format/structure of the JSON output is subject to change.

The available command line options may be seen by passing `-h`/`--help`:

Usage: cassandra-exporter-standalone [-hV] [--enable-collector-timing]
[--enable-per-thread-cpu-times]
[--exclude-system-tables]
[--no-fast-float] [--no-global-labels]
[--no-table-labels] [--cql-address=
[ADDRESS][:PORT]]
[--cql-password=PASSWORD]
[--cql-user=NAME] [--family-help=VALUE]
[--jmx-password=PASSWORD]
[--jmx-service-url=URL] [--jmx-user=NAME]
[--exclude-keyspaces=<excludedKeyspaces>]..
. [-g=LABEL[,LABEL...]]... [-l=[ADDRESS][:
PORT]]... [-t=LABEL[,LABEL...]]...
[-e=EXCLUSION...]...
Usage: cassandra-exporter [-hV] [--enable-collector-timing]
[--enable-per-thread-cpu-times]
[--exclude-system-tables] [--no-fast-float]
[--no-global-labels] [--no-table-labels] [-v]...
[--cql-address=[ADDRESS][:PORT]]
[--cql-password=PASSWORD] [--cql-user=NAME]
[--family-help=VALUE] [--jmx-password=PASSWORD]
[--jmx-service-url=URL] [--jmx-user=NAME]
[--keyspace-metrics=FILTER] [--node-metrics=FILTER]
[--table-metrics=FILTER]
[--exclude-keyspaces=<excludedKeyspaces>]... [-g=LABEL
[,LABEL...]]... [-l=[ADDRESS][:PORT]]... [-t=LABEL[,
LABEL...]]... [-e=EXCLUSION...]...
-g, --global-labels=LABEL[,LABEL...]
Select which global labels to include on all exported
metrics. Valid options are: 'CLUSTER' (cluster name),
'HOST_ID' (UUID of the node), 'NODE' (node endpoint IP
address), 'DATACENTER' (DC name), 'RACK' (rack name).
The default is to include all global labels except
HOST_ID. To disable all global labels use
--no-global-labels.
'NODE' (node endpoint IP address), 'DATACENTER' (DC
name), 'RACK' (rack name). The default is to include
all global labels except HOST_ID. To disable all
global labels use --no-global-labels.
-t, --table-labels=LABEL[,LABEL...]
Select which labels to include on table-level metrics.
Valid options are: 'TABLE_TYPE' (table, view or
Expand All @@ -131,6 +129,20 @@ The available command line options may be seen by passing `-h`/`--help`:
tables & views, compaction-related metrics only). The
default is to include all table labels. To disable all
table labels use --no-table-labels.
--table-metrics=FILTER
Select which table-level metrics to expose. Valid
options are: 'ALL' (all metrics), 'HISTOGRAMS' (only
histograms & summaries), 'NONE' (no metrics). The
default is 'ALL'.
--keyspace-metrics=FILTER
Select which keyspace-level aggregate metrics to expose.
Valid options are: 'ALL' (all metrics), 'HISTOGRAMS'
(only histograms & summaries), 'NONE' (no metrics).
The default is 'HISTOGRAMS'.
--node-metrics=FILTER Select which node-level aggregate metrics to expose.
Valid options are: 'ALL' (all metrics), 'HISTOGRAMS'
(only histograms & summaries), 'NONE' (no metrics).
The default is 'HISTOGRAMS'.
--enable-per-thread-cpu-times
Collect per-thread CPU times, where each thread gets its
own time-series. (EXPERIMENTAL)
Expand All @@ -139,7 +151,6 @@ The available command line options may be seen by passing `-h`/`--help`:
and export the results.
--exclude-keyspaces=<excludedKeyspaces>

--no-global-labels Disable all global labels.
-e, --exclude=EXCLUSION...
Exclude a metric family or MBean from exposition.
EXCLUSION may be the full name of a metric family
Expand All @@ -153,6 +164,7 @@ The available command line options may be seen by passing `-h`/`--help`:
prefixed with '#' are considered comments and are
ignored. This option may be specified more than once
to define multiple exclusions.
--no-global-labels Disable all global labels.
--no-table-labels Disable all table labels.
--no-fast-float Disable the use of fast float -> ascii conversion.
--exclude-system-tables
Expand Down Expand Up @@ -188,11 +200,14 @@ The available command line options may be seen by passing `-h`/`--help`:
--cql-user=NAME CQL authentication user name.
--cql-password=PASSWORD
CQL authentication password.
-v, --verbose Enable verbose logging. Multiple invocations increase
the verbosity.
-h, --help Show this help message and exit.
-V, --version Print version information and exit.




Options may also be provided via an `@`-file:

- *Standalone*
Expand Down Expand Up @@ -254,8 +269,12 @@ For exporters that run as a separate process there is additional overhead of int

The exporter attempts to follow Prometheus' best practices for metric names, labels and data types.

Cassandras built-in aggregate metrics, such as the table-related metrics at the keyspace and node level, are skipped.
Instead only the table-level metrics are exported &mdash; aggregates can be computed on-the-fly using PromQL queries or once using Prometheus recording rules.
Cassandra has keyspace- and node-level metrics that are aggregates of the per-table metrics. By default, only a subset of these
aggregate metrics, specifically histograms, are exposed by *cassandra-exporter*. All other keyspace- and node-level
metrics are skipped in favour of only exporting the per-table metrics. The rationale behind this is that apart from the histograms,
the aggregate metrics are essentially duplicates. If they are needed they may be computed on-the-fly via PromQL or
once, at scrape time, using Prometheus recording rules.


Unlike the metrics exported via JMX, where each table metric has a unique name, Cassandras metrics are coalesced when appropriate so they share the same exported metric family name, opting for *labels* to differentiate individual time series.
For example, each table level metric has a constant name and at minimum a `table` & `keyspace` label, which allows for complex PromQL queries.
Expand Down Expand Up @@ -297,13 +316,13 @@ Element | Value
### Global Labels

The exporter does attach global labels to the exported metrics.
These may be configured with the `--global-labels` (or disabled via `--no-global-labels) CLI option.
These may be configured with the `--global-labels` (or disabled via `--no-global-labels`) CLI option.

These labels are:

- `cassandra_cluster`

The name of the cluster, as specified in cassandra.yaml.
The name of the cluster, as specified in `cassandra.yaml`.

- `cassandra_host_id`

Expand Down
Loading

0 comments on commit 9911b5d

Please sign in to comment.