diff options
Diffstat (limited to 'doc/development/redis.md')
| -rw-r--r-- | doc/development/redis.md | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/doc/development/redis.md b/doc/development/redis.md index 68cab9ac38d..5073d9350e8 100644 --- a/doc/development/redis.md +++ b/doc/development/redis.md @@ -4,7 +4,7 @@ group: unassigned info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments --- -# Redis guidelines +# Redis development guidelines ## Redis instances @@ -56,7 +56,7 @@ the entry, instead of relying on the key changing. ### Multi-key commands -We don't use Redis Cluster, but support for it is tracked in [this issue](https://gitlab.com/gitlab-org/gitlab/-/issues/118820). +GitLab supports Redis Cluster only for the Redis [rate-limiting](https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/redis/rate_limiting.rb) type, introduced in [epic 823](https://gitlab.com/groups/gitlab-com/gl-infra/-/epics/823). This imposes an additional constraint on naming: where GitLab is performing operations that require several keys to be held on the same Redis server - for @@ -77,6 +77,10 @@ with the [`RedisClusterValidator`](https://gitlab.com/gitlab-org/gitlab/-/blob/m which is enabled for the `cache` and `shared_state` [Redis instances](https://docs.gitlab.com/omnibus/settings/redis.html#running-with-multiple-redis-instances).. +Developers are highly encouraged to use [hash-tags](https://redis.io/docs/reference/cluster-spec/#hash-tags) +where appropriate to facilitate future adoption of Redis Cluster in more Redis types. For example, the Namespace model uses hash-tags +for its [config cache keys](https://gitlab.com/gitlab-org/gitlab/-/blob/1a12337058f260d38405886d82da5e8bb5d8da0b/app/models/namespace.rb#L786). + ## Redis in structured logging For GitLab Team Members: There are <i class="fa fa-youtube-play youtube" aria-hidden="true"></i> @@ -188,6 +192,26 @@ it 'avoids N+1 Redis calls to forks_count key' do end ``` +You also can use special matchers `exceed_redis_calls_limit` and +`exceed_redis_command_calls_limit` to define an upper limit for +a number of Redis calls: + +```ruby +it 'avoids N+1 Redis calls' do + control = RedisCommands::Recorder.new { visit_page } + + expect(control).not_to exceed_redis_calls_limit(1) +end +``` + +```ruby +it 'avoids N+1 sadd Redis calls' do + control = RedisCommands::Recorder.new { visit_page } + + expect(control).not_to exceed_redis_command_calls_limit(:sadd, 1) +end +``` + These tests can help to identify N+1 problems related to Redis calls, and make sure that the fix for them works as expected. |