• Format
  • Authentication
  • TLS
  • Storage
  • Git
    • cat-file cache
  • gitaly-ruby
  • GitLab Shell
  • Prometheus
  • Logging
• Concurrency

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.

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

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.

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, such as /home/git/repositories. They contain bare repositories managed by GitLab with names, such as 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 (the default and recommended configuration) storage paths defined in Gitaly’s config.toml must match those in gitlab.yml.

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.

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.

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.

Example:

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

Prometheus

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

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.

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.

Example:

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