fix: reduce impact of GetPrebuildMetrics on database (#19694)

cstyan · web-flow · commit 0ec9df390b00 · 2025-09-04T13:43:50.000-07:00
see coder/internal#959 but the tl; dr is: - we call this DB query on an interval (every 15s) and it would be called on each coderd replica as well - the generated values update very infrequently (for our most used internal template I saw the builds created/claimed update twice in a 1h period) - we have no index on the initiator ID, so this query has to scan the entire workspace_builds table on every request In reality this should likely just be a Prometheus metric, and Prometheus can handle the counter reset behaviour at query time, but for now this should at least cut the load of the query to 25% of it's current impact. --------- Signed-off-by: Callum Styan <callumstyan@gmail.com>
diff --git a/coderd/database/dump.sql b/coderd/database/dump.sql
diff --git a/coderd/database/migrations/000363_workspace_build_initiator_index.down.sql b/coderd/database/migrations/000363_workspace_build_initiator_index.down.sql
@@ -0,0 +1,2 @@
+-- Remove index on workspace_builds.initiator_id
+DROP INDEX IF EXISTS idx_workspace_builds_initiator_id;
diff --git a/coderd/database/migrations/000363_workspace_build_initiator_index.up.sql b/coderd/database/migrations/000363_workspace_build_initiator_index.up.sql
@@ -0,0 +1,6 @@
+-- Add index on workspace_builds.initiator_id to optimize prebuild queries
+-- This will dramatically improve performance for:
+-- - GetPrebuildMetrics (called every 15 seconds)
+-- - Any other queries using workspace_prebuild_builds view
+-- - Provisioner job queue prioritization
+CREATE INDEX idx_workspace_builds_initiator_id ON workspace_builds (initiator_id);
diff --git a/enterprise/coderd/prebuilds/metricscollector.go b/enterprise/coderd/prebuilds/metricscollector.go
@@ -105,7 +105,7 @@ var (
 )
 
 const (
-	metricsUpdateInterval = time.Second * 15
+	metricsUpdateInterval = time.Second * 60
 	metricsUpdateTimeout  = time.Second * 10
 )
 

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+-- Remove index on workspace_builds.initiator_id`
	`2`	`+DROP INDEX IF EXISTS idx_workspace_builds_initiator_id;`
Original file line number	Diff line number	Diff line change
`@@ -105,7 +105,7 @@ var (`
`105`	`105`	`)`
`106`	`106`
`107`	`107`	`const (`
`108`		`- metricsUpdateInterval = time.Second * 15`
	`108`	`+ metricsUpdateInterval = time.Second * 60`
`109`	`109`	`metricsUpdateTimeout = time.Second * 10`
`110`	`110`	`)`
`111`	`111`