Merge branch 'master' into 'refactor-snippets-finder'refactor-snippets-finder

# Conflicts:
#   spec/models/project_spec.rb

1 files changed, 11 insertions, 0 deletions

diff --git a/app/models/postgresql/replication_slot.rb b/app/models/postgresql/replication_slot.rb
index 70c7432e6b5..e264fe88e47 100644
--- a/app/models/postgresql/replication_slot.rb
+++ b/app/models/postgresql/replication_slot.rb
@@ -4,6 +4,15 @@ module Postgresql
   class ReplicationSlot < ActiveRecord::Base
     self.table_name = 'pg_replication_slots'
 
+    # Returns true if there are any replication slots in use.
+    # PostgreSQL-compatible databases such as Aurora don't support
+    # replication slots, so this will return false as well.
+    def self.in_use?
+      transaction { exists? }
+    rescue ActiveRecord::StatementInvalid
+      false
+    end
+
     # Returns true if the lag observed across all replication slots exceeds a
     # given threshold.
     #
@@ -11,6 +20,8 @@ module Postgresql
     #       statistics it takes between 1 and 5 seconds to replicate around
     #       100 MB of data.
     def self.lag_too_great?(max = 100.megabytes)
+      return false unless in_use?
+
       lag_function = "#{Gitlab::Database.pg_wal_lsn_diff}" \
         "(#{Gitlab::Database.pg_current_wal_insert_lsn}(), restart_lsn)::bigint"