Agent Check: TiDB

Overview

Connect TiDB cluster to Datadog in order to:

• Collect key TiDB metrics of your cluster.
• Collect logs of your cluster, such as TiDB/TiKV/TiFlash logs and slow query logs.
• Visualize cluster performance on the provided dashboard.

Note:

• TiDB 4.0+ is required for this integration.
• For TiDB Cloud, see the TiDB Cloud Integration.

Setup

Installation

First, download and launch the Datadog Agent.

Then, manually install the TiDB check. Instructions vary depending on the environment.

Run datadog-agent integration install -t datadog-tidb==<INTEGRATION_VERSION>.

Configuration

Metric collection

1. Edit the tidb.d/conf.yaml file in the conf.d/ folder at the root of your Agent's configuration directory to start collecting your TiDB performance data. See the sample tidb.d/conf.yaml for all available configuration options.

The sample tidb.d/conf.yaml only configures the PD instance. You need to manually configure the other instances in the TiDB cluster. Like this:

init_config:

instances:

  - pd_metric_url: http://localhost:2379/metrics
    send_distribution_buckets: true
    tags:
      - cluster_name:cluster01

  - tidb_metric_url: http://localhost:10080/metrics
    send_distribution_buckets: true
    tags:
      - cluster_name:cluster01

  - tikv_metric_url: http://localhost:20180/metrics
    send_distribution_buckets: true
    tags:
      - cluster_name:cluster01

  - tiflash_metric_url: http://localhost:8234/metrics
    send_distribution_buckets: true
    tags:
      - cluster_name:cluster01

  - tiflash_proxy_metric_url: http://localhost:20292/metrics
    send_distribution_buckets: true
    tags:
      - cluster_name:cluster01

3. Restart the Agent.

Log collection

Available for Agent versions >6.0

1. Collecting logs is disabled by default in the Datadog Agent, enable it in your datadog.yaml file:

   logs_enabled: true

2. Add this configuration block to your tidb.d/conf.yaml file to start collecting your TiDB logs:

   logs:
    # pd log
    - type: file
      path: "/tidb-deploy/pd-2379/log/pd*.log"
      service: "tidb-cluster"
      source: "pd"
   
    # tikv log
    - type: file
      path: "/tidb-deploy/tikv-20160/log/tikv*.log"
      service: "tidb-cluster"
      source: "tikv"
   
    # tidb log
    - type: file
      path: "/tidb-deploy/tidb-4000/log/tidb*.log"
      service: "tidb-cluster"
      source: "tidb"
      exclude_paths:
        - /tidb-deploy/tidb-4000/log/tidb_slow_query.log
    - type: file
      path: "/tidb-deploy/tidb-4000/log/tidb_slow_query*.log"
      service: "tidb-cluster"
      source: "tidb"
      log_processing_rules:
        - type: multi_line
          name: new_log_start_with_datetime
          pattern: '#\sTime:'
      tags:
        - "custom_format:tidb_slow_query"
   
    # tiflash log
    - type: file
      path: "/tidb-deploy/tiflash-9000/log/tiflash*.log"
      service: "tidb-cluster"
      source: "tiflash"

   Change the path and service according to your cluster's configuration.

   Use these commands to show all log path:

   # show deploying directories
   tiup cluster display <YOUR_CLUSTER_NAME>
   # find specific logging file path by command arguments
   ps -fwwp <TIDB_PROCESS_PID/PD_PROCESS_PID/etc.>

3. Restart the Agent.

Validation

Run the Agent's status subcommand and look for tidb under the Checks section.

Data Collected

Metrics

See metadata.csv for a list of metrics provided by this check.

It is possible to use the metrics configuration option to collect additional metrics from a TiDB cluster.

Events

TiDB check does not include any events.

Service Checks

Service Checks are based on tidb_cluster.prometheus.health metrics. This check is controlled by the health_service_check config and default to true. You can modify this behavior in tidb.yml file.

See service_checks.json for a list of service checks provided by this integration.

Troubleshooting

Missing CPU and Memory metrics for TiKV and TiFlash instances on macOS

CPU and Memory metrics are not provided for TiKV and TiFlash instances in the following cases:

• Running TiKV or TiFlash instances with tiup playground on macOS.
• Running TiKV or TiFlash instances with docker-compose up on a new Apple M1 machine.

Too many metrics

The TiDB check enables Datadog's distribution metric type by default. This part of data is quite large and may consume lots of resources. You can modify this behavior in tidb.yml file:

• send_distribution_buckets: false

Since there are many important metrics in a TiDB cluster, the TiDB check sets max_returned_metrics to 10000 by default. You can decrease max_returned_metrics in tidb.yml file if necessary:

• max_returned_metrics: 1000

Need help? Contact Datadog support.