Parsing GitLab logs with jq

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We recommend using log aggregation and search tools like Kibana and Splunk whenever possible, but if they are not available you can still quickly parse GitLab logs in JSON format using jq.

note
Specifically for summarizing error events and basic usage statistics, the GitLab Support Team provides the specialised fast-stats tool.

What is JQ?

As noted in its manual, jq is a command-line JSON processor. The following examples include use cases targeted for parsing GitLab log files.

Parsing Logs

The examples listed below address their respective log files by their relative Linux package installation paths and default filenames. Find the respective full paths in the GitLab logs sections.

Compressed logs

When log files are rotated, they are renamed in Unix timestamp format and compressed with gzip. The resulting file name looks like @40000000624492fa18da6f34.s. These files must be handled differently before parsing, than the more recent log files:

  • To uncompress the file, use gunzip -S .s @40000000624492fa18da6f34.s, replacing the filename with your compressed log file’s name.
  • To read or pipe the file directly, use zcat or zless.
  • To search file contents, use zgrep.

General Commands

Pipe colorized jq output into less 

jq . <FILE> -C | less -R

Search for a term and pretty-print all matching lines 

grep <TERM> <FILE> | jq .

Skip invalid lines of JSON 

jq -cR 'fromjson?' file.json | jq <COMMAND>

By default jq errors out when it encounters a line that is not valid JSON. This skips over all invalid lines and parses the rest. 

cat log.json | (head -1; tail -1) | jq '.time'

Use zcat if the file has been rotated and compressed: 

zcat @400000006026b71d1a7af804.s | (head -1; tail -1) | jq '.time'

zcat some_json.log.25.gz | (head -1; tail -1) | jq '.time'

Get activity for correlation ID across multiple JSON logs in chronological order 

grep -hR <correlationID> | jq -c -R 'fromjson?' | jq -C -s 'sort_by(.time)'  | less -R

Parsing gitlab-rails/production_json.log and gitlab-rails/api_json.log

Find all requests with a 5XX status code 

jq 'select(.status >= 500)' <FILE>

Top 10 slowest requests 

jq -s 'sort_by(-.duration_s) | limit(10; .[])' <FILE>

grep <PROJECT_NAME> <FILE> | jq .

Find all requests with a total duration > 5 seconds 

jq 'select(.duration_s > 5000)' <FILE>

Find all project requests with more than 5 Gitaly calls 

grep <PROJECT_NAME> <FILE> | jq 'select(.gitaly_calls > 5)'

Find all requests with a Gitaly duration > 10 seconds 

jq 'select(.gitaly_duration_s > 10000)' <FILE>

Find all requests with a queue duration > 10 seconds 

jq 'select(.queue_duration_s > 10000)' <FILE>

Top 10 requests by # of Gitaly calls 

jq -s 'map(select(.gitaly_calls != null)) | sort_by(-.gitaly_calls) | limit(10; .[])' <FILE>

Output a specific time range 

jq 'select(.time >= "2023-01-10T00:00:00Z" and .time <= "2023-01-10T12:00:00Z")' <FILE>

Parsing gitlab-rails/production_json.log 

jq -s -r 'group_by(.controller+.action) | sort_by(-length) | limit(3; .[]) | sort_by(-.duration_s) | "CT: \(length)\tMETHOD: \(.[0].controller)#\(.[0].action)\tDURS: \(.[0].duration_s),  \(.[1].duration_s),  \(.[2].duration_s)"' production_json.log

Example output 

CT: 2721   METHOD: SessionsController#new  DURS: 844.06,  713.81,  704.66
CT: 2435   METHOD: MetricsController#index DURS: 299.29,  284.01,  158.57
CT: 1328   METHOD: Projects::NotesController#index DURS: 403.99,  386.29,  384.39

Parsing gitlab-rails/api_json.log 

jq -s -r 'group_by(.route) | sort_by(-length) | limit(3; .[]) | sort_by(-.duration_s) | "CT: \(length)\tROUTE: \(.[0].route)\tDURS: \(.[0].duration_s),  \(.[1].duration_s),  \(.[2].duration_s)"' api_json.log

Example output 

CT: 2472 ROUTE: /api/:version/internal/allowed   DURS: 56402.65,  38411.43,  19500.41
CT: 297  ROUTE: /api/:version/projects/:id/repository/tags       DURS: 731.39,  685.57,  480.86
CT: 190  ROUTE: /api/:version/projects/:id/repository/commits    DURS: 1079.02,  979.68,  958.21

jq --raw-output 'select(.remote_ip != "127.0.0.1") | [.remote_ip, .username, .route, .ua] | @tsv' api_json.log |
  sort | uniq -c | sort -n | tail

Example output: 

  89 1.2.3.4, 127.0.0.1  some_user  /api/:version/projects/:id/pipelines  # plus browser details; OK
 567 5.6.7.8, 127.0.0.1      /api/:version/jobs/:id/trace gitlab-runner   # plus version details; OK
1234 98.76.54.31, 127.0.0.1  some_bot  /api/:version/projects/:id/repository/files/:file_path/raw

This example shows a custom tool or script causing an unexpectedly high number of requests. User agents in this situation can be specialized third-party clients, or general tools like curl.

You can also use fast-stats top to extract performance statistics for those users or bots.

Parsing gitlab-rails/importer.log

To troubleshoot project imports or migrations, run this command: 

jq 'select(.project_path == "<namespace>/<project>").error_messages' importer.log

For common issues, see troubleshooting.

Parsing gitlab-workhorse/current 

jq --raw-output 'select(.remote_ip != "127.0.0.1") | [.remote_ip, .uri, .user_agent] | @tsv' current |
  sort | uniq -c | sort -n | tail

Similar to the API ua example, many unexpected user agents in this output indicate unoptimized scripts. Expected user agents include gitlab-runner, GitLab-Shell, and browsers.

The performance impact of runners checking for new jobs can be reduced by increasing the check_interval setting, for example.

Parsing gitlab-rails/geo.log

Find most common Geo sync errors

If the geo:status Rake task repeatedly reports that some items never reach 100%, the following command helps to focus on the most common errors. 

jq --raw-output 'select(.severity == "ERROR") | [.project_path, .class, .message, .error] | @tsv' geo.log | sort | uniq -c | sort | tail

Refer to our Geo troubleshooting page for advice about specific error messages.

Parsing gitaly/current

Use the following examples to troubleshoot Gitaly.

Find all Gitaly requests sent from web UI 

jq 'select(."grpc.meta.client_name" == "gitlab-web")' current

Find all failed Gitaly requests 

jq 'select(."grpc.code" != null and ."grpc.code" != "OK")' current

Find all requests that took longer than 30 seconds 

jq 'select(."grpc.time_ms" > 30000)' current

jq --raw-output --slurp '
  map(
    select(
      ."grpc.request.glProjectPath" != null
      and ."grpc.request.glProjectPath" != ""
      and ."grpc.time_ms" != null
    )
  )
  | group_by(."grpc.request.glProjectPath")
  | sort_by(-length)
  | limit(10; .[])
  | sort_by(-."grpc.time_ms")
  | [
      length,
      .[0]."grpc.time_ms",
      .[1]."grpc.time_ms",
      .[2]."grpc.time_ms",
      .[0]."grpc.request.glProjectPath"
    ]
  | @sh' current |
  awk 'BEGIN { printf "%7s %10s %10s %10s\t%s\n", "CT", "MAX DURS", "", "", "PROJECT" }
  { printf "%7u %7u ms, %7u ms, %7u ms\t%s\n", $1, $2, $3, $4, $5 }'

Example output 

   CT    MAX DURS                              PROJECT
  206    4898 ms,    1101 ms,    1032 ms      'groupD/project4'
  109    1420 ms,     962 ms,     875 ms      'groupEF/project56'
  663     106 ms,      96 ms,      94 ms      'groupABC/project123'
  ...

Types of user and project activity overview 

jq --raw-output '[.username, ."grpc.method", ."grpc.request.glProjectPath"] | @tsv' current | sort | uniq -c | sort -n

Find all projects affected by a fatal Git problem 

grep "fatal: " current |
  jq '."grpc.request.glProjectPath"' |
  sort | uniq

Parsing gitlab-shell/gitlab-shell.log

For investigating Git calls through SSH.

Find the top 20 calls by project and user: 

jq --raw-output --slurp '
  map(
    select(
      .username != null and
      .gl_project_path !=null
    )
  )
  | group_by(.username+.gl_project_path)
  | sort_by(-length)
  | limit(20; .[])
  | "count: \(length)\tuser: \(.[0].username)\tproject: \(.[0].gl_project_path)" ' \
  gitlab-shell.log

Find the top 20 calls by project, user, and command: 

jq --raw-output --slurp '
  map(
    select(
      .command  != null and
      .username != null and
      .gl_project_path !=null
    )
  )
  | group_by(.username+.gl_project_path+.command)
  | sort_by(-length)
  | limit(20; .[])
  | "count: \(length)\tcommand: \(.[0].command)\tuser: \(.[0].username)\tproject: \(.[0].gl_project_path)" ' \
  gitlab-shell.log