diff options
Diffstat (limited to 'config/initializers/database_config.rb')
| -rw-r--r-- | config/initializers/database_config.rb | 19 |
1 files changed, 5 insertions, 14 deletions
diff --git a/config/initializers/database_config.rb b/config/initializers/database_config.rb index cccd4335a7d..a91f67224d7 100644 --- a/config/initializers/database_config.rb +++ b/config/initializers/database_config.rb @@ -20,21 +20,12 @@ Gitlab.ee do end end -# Because of the way Ruby on Rails manages database connections, it is -# important that we have at least as many connections as we have -# threads. While there is a 'pool' setting in database.yml, it is not -# very practical because you need to maintain it in tandem with the -# number of application threads. Because of this we override the number -# of allowed connections in the database connection pool based on the -# configured number of application threads. +# We configure the database connection pool size automatically based on the +# configured concurrency. We also add some headroom, to make sure we don't run +# out of connections when more threads besides the 'user-facing' ones are +# running. # -# Gitlab::Runtime.max_threads is the number of "user facing" application -# threads the process has been configured with. We also have auxiliary -# threads that use database connections. Because it is not practical to -# keep an accurate count of the number auxiliary threads as the -# application evolves over time, we just add a fixed headroom to the -# number of user-facing threads. It is OK if this number is too large -# because connections are instantiated lazily. +# Read more about this in doc/development/database/client_side_connection_pool.md headroom = (ENV["DB_POOL_HEADROOM"].presence || 10).to_i calculated_pool_size = Gitlab::Runtime.max_threads + headroom |