Gitaly reference

Gitaly is configured via a TOML configuration file. Unlike installations from source, in Omnibus GitLab, you would not edit this file directly.

The configuration file is passed as an argument to the gitaly executable. This is usually done by either Omnibus GitLab or your init script.

An example configuration file can be found in the Gitaly project.

Format

At the top level, config.toml defines the items described on the table below.

Name Type Required Description
socket_path string yes (if listen_addr is not set) A path which Gitaly should open a Unix socket.
listen_addr string yes (if socket_path is not set) TCP address for Gitaly to listen on.
tls_listen_addr string no TCP over TLS address for Gitaly to listen on.
bin_dir string yes Directory containing Gitaly’s executables.
prometheus_listen_addr string no TCP listen address for Prometheus metrics. If not set, no Prometheus listener is started.

For example:

socket_path = "/home/git/gitlab/tmp/sockets/private/gitaly.socket"
listen_addr = "localhost:9999"
tls_listen_addr = "localhost:8888"
bin_dir = "/home/git/gitaly"
prometheus_listen_addr = "localhost:9236"

Authentication

Gitaly can be configured to reject requests that do not contain a specific bearer token in their headers. This is a security measure to be used when serving requests over TCP:

[auth]
# A non-empty token enables authentication.
token = "the secret token"

Authentication is disabled when the token setting in config.toml is absent or an empty string.

It is possible to temporarily disable authentication with the transitioning setting. This allows you to monitor if all clients are authenticating correctly without causing a service outage for clients that are not configured correctly yet:

[auth]
token = "the secret token"
transitioning = true
cautionRemember to disable transitioning when you are done changing your token settings.

All authentication attempts are counted in Prometheus under the gitaly_authentications_total metric.

TLS

Gitaly supports TLS encryption. You need to bring your own certificates as this isn’t provided automatically.

Name Type Required Description
certificate_path string no Path to the certificate.
key_path string no Path to the key.
tls_listen_addr = "localhost:8888"

[tls]
certificate_path = '/home/git/cert.cert'
key_path = '/home/git/key.pem'

Read more about TLS in Gitaly.

Storage

GitLab repositories are grouped into directories known as “storages” (e.g., /home/git/repositories) containing bare repositories managed by GitLab with names (e.g., default).

These names and paths are also defined in the gitlab.yml configuration file of GitLab. When you run Gitaly on the same machine as GitLab, which is the default and recommended configuration, storage paths defined in Gitaly’s config.toml must match those in gitlab.yml.

Name Type Required Description
storage array yes An array of storage shards.
path string yes The path to the storage shard.
name string yes The name of the storage shard.

For example:

[[storage]]
path = "/path/to/storage/repositories"
name = "my_shard"

[[storage]]
path = "/path/to/other/repositories"
name = "other_storage"

Git

The following values can be set in the [git] section of the configuration file.

Name Type Required Description
bin_path string no Path to Git binary. If not set, is resolved using PATH.
catfile_cache_size integer no Maximum number of cached cat-file processes. Default is 100.

cat-file cache

A lot of Gitaly RPCs need to look up Git objects from repositories. Most of the time we use git cat-file --batch processes for that. For better performance, Gitaly can re-use these git cat-file processes across RPC calls. Previously used processes are kept around in a “Git cat-file cache”. To control how much system resources this uses, we have a maximum number of cat-file processes that can go into the cache.

The default limit is 100 cat-files, which constitute a pair of git cat-file --batch and git cat-file --batch-check processes. If you are seeing errors complaining about “too many open files”, or an inability to create new processes, you may want to lower this limit.

Ideally, the number should be large enough to handle normal traffic. If you raise the limit, you should measure the cache hit ratio before and after. If the hit ratio does not improve, the higher limit is probably not making a meaningful difference. Here is an example Prometheus query to see the hit rate:

sum(rate(gitaly_catfile_cache_total{type="hit"}[5m])) / sum(rate(gitaly_catfile_cache_total{type=~"(hit)|(miss)"}[5m]))

gitaly-ruby

A Gitaly process uses one or more gitaly-ruby helper processes to execute RPC’s implemented in Ruby instead of Go. The [gitaly-ruby] section of the configuration file contains settings for these helper processes.

These processes are known to occasionally suffer from memory leaks. Gitaly restarts its gitaly-ruby helpers when their memory exceeds the max_rss limit.

Name Type Required Description
dir string yes Path to where gitaly-ruby is installed (needed to boot the process).
max_rss integer no Resident set size limit that triggers a gitaly-ruby restart, in bytes. Default is 200000000 (200MB).
graceful_restart_timeout string no Grace period before a gitaly-ruby process is forcibly terminated after exceeding max_rss. Default is 10m (10 minutes).
restart_delay string no Time that gitaly-ruby memory must remain high before a restart. Default is 5m (5 minutes).
num_workers integer no Number of gitaly-ruby worker processes. Try increasing this number in case of ResourceExhausted errors. Default is 2, minimum is 2.
linguist_languages_path string no Override for dynamic languages.json discovery. Defaults to an empty string (use of dynamic discovery).

Example:

[gitaly-ruby]
dir = "/home/git/gitaly/ruby"
max_rss = 200000000
graceful_restart_timeout = "10m"
restart_delay = "5m"
num_workers = 2

GitLab Shell

For historical reasons GitLab Shell contains the Git hooks that allow GitLab to validate and react to Git pushes. Because Gitaly “owns” Git pushes, GitLab Shell must therefore be installed alongside Gitaly. We plan to simplify this.

Name Type Required Description
dir string yes The directory where GitLab Shell is installed.

Example:

[gitlab-shell]
dir = "/home/git/gitlab-shell"

Prometheus

You can optionally configure Gitaly to record histogram latencies on GRPC method calls in Prometheus.

Name Type Required Description
grpc_latency_buckets array no Prometheus stores each observation in a bucket, which means you’d get an approximation of latency. Optimizing the buckets gives more control over the accuracy of the approximation.

Example:

prometheus_listen_addr = "localhost:9236"

[prometheus]
grpc_latency_buckets = [0.001, 0.005, 0.025, 0.1, 0.5, 1.0, 10.0, 30.0, 60.0, 300.0, 1500.0]

Logging

The following values configure logging in Gitaly under the [logging] section.

Name Type Required Description
format string no Log format: text or json. Default: text.
level string no Log level: debug, info, warn, error, fatal, or panic. Default: info.
sentry_dsn string no Sentry DSN for exception monitoring.
sentry_environment string no Sentry Environment for exception monitoring.
ruby_sentry_dsn string no Sentry DSN for gitaly-ruby exception monitoring.

While the main Gitaly application logs go to stdout, there are some extra log files that go to a configured directory, like the GitLab Shell logs. GitLab Shell does not support panic or trace level logs:

  • panic falls back to error.
  • trace falls back to debug.
  • Any other invalid log levels default to info.

Example:

[logging]
level = "warn"
dir = "/home/gitaly/logs"
format = "json"
sentry_dsn = "https://<key>:<secret>@sentry.io/<project>"
ruby_sentry_dsn = "https://<key>:<secret>@sentry.io/<project>"

Concurrency

You can adjust the concurrency of each RPC endpoint.

Name Type Required Description
concurrency array yes An array of RPC endpoints.
rpc string no The name of the RPC endpoint (/gitaly.RepositoryService/GarbageCollect).
max_per_repo integer no Concurrency per RPC per repository.

Example:

[[concurrency]]
rpc = "/gitaly.RepositoryService/GarbageCollect"
max_per_repo = 1