Ethan 15f2fa55c6 perf(coderd/x/chatd): add process-wide config cache for hot DB queries (#23272) ...

## Summary

Adds a process-wide cache for three hot database queries in `chatd` that
were hitting Postgres on **every chat turn** despite returning
rarely-changing configuration data:

| Query | Before (50k turns) | After | Reduction |
|---|---|---|---|
| `GetEnabledChatProviders` | ~98.6k calls | ~500-1000 | ~99% |
| `GetChatModelConfigByID` | ~49.2k calls | ~500-1000 | ~98% |
| `GetUserChatCustomPrompt` | ~46.7k calls | ~1000-2000 | ~97% |

These were identified via `coder exp scaletest chat` (5000 concurrent
chats × 10 turns) as the dominant source of Postgres load during chat
processing.

## Design

Follows the established **webpush subscription cache pattern**
(`coderd/webpush/webpush.go`):
- `sync.RWMutex` + `tailscale.com/util/singleflight` (generic) +
generation-based stale prevention + TTL
- 10s TTL for provider/model config, 5s TTL for user prompts
- Negative caching for `sql.ErrNoRows` on user prompts (the common case
— most users don't set custom prompts)
- Deep-clones `ChatModelConfig.Options` (`json.RawMessage` = `[]byte`)
on both store and read paths

### Invalidation

Single pubsub channel (`chat:config_change`) with kind discriminator for
cross-replica cache invalidation. Seven publish points in
`coderd/chats.go` cover all admin mutation endpoints
(create/update/delete for providers and model configs, put for user
prompts).

_This PR was generated with mux and was reviewed by a human_

2026-03-26 18:04:53 +11:00

..

agentapi

fix: limit calls to GetWorkspaceAgentByID in agentapi (#23015)

2026-03-20 15:42:05 -05:00

agentmetrics

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

aibridge

feat: aibridge BYOK (#23013)

2026-03-25 14:17:56 -04:00

aiseats

feat: track ai seat usage (#22682)

2026-03-16 12:36:26 -05:00

apidoc

feat: add filtering by service account (#23468)

2026-03-24 10:13:25 -08:00

apikey

fix: initialize API key LastUsed to Unix epoch instead of zero time (#22327)

2026-03-02 16:02:01 +01:00

appearance

fix: make cli respect deployment --docs-url (#14568)

2024-09-18 21:47:53 +10:00

audit

chore: add audit log entry when ai seat is consumed (#22683)

2026-03-16 15:30:25 -05:00

autobuild

fix: use "idle timeout" as task auto-pause reason (#22287)

2026-02-24 16:45:56 +00:00

awsidentity

fix: add new aws regions to instance identity (#10434)

2023-10-30 19:44:29 +00:00

azureidentity

chore: update azure certs (#21265)

2025-12-15 13:44:44 -09:00

boundaryusage

fix: make boundary usage telemetry collection atomic (#21907)

2026-02-06 09:52:17 -07:00

cachecompress

fix(site): avoid duplicating bin download headers (#22981)

2026-03-13 00:22:55 +11:00

coderdtest

feat: add filtering by service account (#23468)

2026-03-24 10:13:25 -08:00

connectionlog

fix: avoid connection logging crashes in agent (#20307)

2025-10-16 01:56:43 +11:00

cryptokeys

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

database

perf(coderd/x/chatd): persist workspace agent binding across chat turns (#23274)

2026-03-26 17:22:38 +11:00

devtunnel

chore: remove unnecessary loop variable captures (#22180)

2026-02-19 09:02:19 +00:00

dynamicparameters

refactor: replace sort.Strings with slices.Sort (#23457)

2026-03-23 23:19:23 +02:00

entitlements

feat: add Prometheus metrics for license warnings and errors (#21749)

2026-01-29 13:50:15 +01:00

externalauth

feat: add head_branch to pull request diff status (#23076)

2026-03-14 17:24:19 +00:00

files

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

gitsshkey

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

healthcheck

refactor(healthcheck): reduce test boilerplate with healthyChecker helper (#23028)

2026-03-13 10:40:57 +00:00

httpapi

feat: add labels to chats (#23594)

2026-03-25 17:26:26 +00:00

httpmw

fix(coderd/httpmw): return 500 for internal auth errors (#23352)

2026-03-24 12:37:17 +11:00

idpsync

test: remove unnecessary dbauthz.AsSystemRestricted calls in tests (#22663)

2026-03-05 20:29:49 +00:00

jobreaper

refactor: extract test helpers in coderd/jobreaper to reduce duplication (#23001)

2026-03-19 21:51:26 +00:00

jwtutils

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

mcp

feat: expose MCP tool annotations for tool grouping (#23195)

2026-03-18 10:21:45 +00:00

metricscache

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

notifications

refactor: replace sort.Strings with slices.Sort (#23457)

2026-03-23 23:19:23 +02:00

oauth2provider

test: share coderdtest instances in OAuth2 validation tests (#23455)

2026-03-23 21:03:34 +00:00

oauthpki

fix(coderd): support string type for oidc response's expires_in json property (#20152)

2025-10-15 17:37:37 +00:00

portsharing

fix: properly convert max port share level for oss (#13261)

2024-05-13 14:37:51 -04:00

pproflabel

chore: add tallyman events for ai seat tracking (#22689)

2026-03-18 09:30:22 -05:00

prebuilds

chore: remove unnecessary loop variable captures (#22180)

2026-02-19 09:02:19 +00:00

prometheusmetrics

refactor: replace sort.Strings with slices.Sort (#23457)

2026-03-23 23:19:23 +02:00

promoauth

fix!: remove deprecated prometheus metrics (#21788)

2026-01-30 13:30:06 +01:00

provisionerdserver

feat: add merge_strategy support for coder_env resources (#23107)

2026-03-18 15:43:28 +01:00

provisionerkey

chore!: ensure consistent secret token generation and hashing (#20388)

2025-10-23 15:38:49 -05:00

proxyhealth

feat: add csp headers for embedded apps (#18374)

2025-06-17 09:00:32 -08:00

pubsub

perf(coderd/x/chatd): add process-wide config cache for hot DB queries (#23272)

2026-03-26 18:04:53 +11:00

rbac

chore: add permissions to coder:workspace.* scopes for functionality (#23515)

2026-03-25 13:46:58 -05:00

render

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

runtimeconfig

chore(coderd/runtimeconfig): remove dbmem from tests (#18790)

2025-07-08 14:31:05 +00:00

schedule

chore: remove unnecessary loop variable captures (#22180)

2026-02-19 09:02:19 +00:00

searchquery

feat: add filtering by service account (#23468)

2026-03-24 10:13:25 -08:00

taskname

fix(coderd): strip markdown code fences from Anthropic task name responses (#23024)

2026-03-13 17:35:26 +00:00

telemetry

feat: add telemetry for task lifecycle events (#21922)

2026-02-24 17:04:42 +00:00

testdata

feat: add flag to disable template insights (#20940)

2025-12-14 03:00:03 +00:00

tracing

fix: StatusWriter Unwrap and process output error recovery (#23383)

2026-03-20 20:00:55 +00:00

updatecheck

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

usage

chore: add tallyman events for ai seat tracking (#22689)

2026-03-18 09:30:22 -05:00

userpassword

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

util

fix(coderd): actually wire the chat template allowlist into tools (#23626)

2026-03-25 22:15:27 +00:00

webpush

perf(coderd): reduce duplicated reads in push and webpush paths (#23115)

2026-03-17 13:50:47 +11:00

workspaceapps

chore: switch agent gone response from 502 to 404 (#23090)

2026-03-25 09:57:28 -04:00

workspacestats

fix: limit calls to GetWorkspaceAgentByID in agentapi (#23015)

2026-03-20 15:42:05 -05:00

wsbuilder

fix: mark presets as validation_failed to prevent endless prebuild retries (#22085)

2026-02-27 14:26:48 +00:00

wspubsub

feat: add WatchAllWorkspaceBuilds endpoint for autostart scaletests (#22057)

2026-03-13 20:37:41 -07:00

x

perf(coderd/x/chatd): add process-wide config cache for hot DB queries (#23272)

2026-03-26 18:04:53 +11:00

activitybump_test.go

test: add testutil.WaitBuffer and replace time.Sleep in tests (#22922)

2026-03-12 18:07:52 +02:00

aitasks_internal_test.go

fix: set codersdk.Task current_state during task initialization (#20692)

2025-11-17 13:24:12 +00:00

aitasks_test.go

fix: return 409 Conflict instead of 502 when task agent is busy (#23424)

2026-03-23 09:52:34 +00:00

aitasks.go

fix: return 409 Conflict instead of 502 when task agent is busy (#23424)

2026-03-23 09:52:34 +00:00

apikey_scopes_validation_test.go

feat: add multi-scope support to API keys (#19917)

2025-09-26 11:56:34 +02:00

apikey_test.go

fix(coderd): use dbtime.Now() instead of time.Now() in test assertions against DB timestamps (#22685)

2026-03-06 09:14:11 +00:00

apikey.go

feat(coderd): filter expired API tokens server-side (#22263)

2026-02-24 15:27:03 +00:00

apiroot.go

…

audit_internal_test.go

chore: add sql filter to fetching audit logs (#14070)

2024-08-01 12:07:19 -05:00

audit_test.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

audit.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

authorize_test.go

feat: add an organization member permission level (#19953)

2025-10-27 17:14:16 -06:00

authorize.go

feat: add experimental agents support (#22290)

2026-02-27 16:50:56 +00:00

client_test.go

…

coderd_internal_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

coderd_test.go

chore: switch agent gone response from 502 to 404 (#23090)

2026-03-25 09:57:28 -04:00

coderd.go

feat: add deployment-wide template allowlist for chats (#23262)

2026-03-25 15:19:17 +00:00

csp.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

debug_test.go

feat(coderd): add consolidated /debug/profile endpoint for pprof collection (#22892)

2026-03-13 14:09:39 +00:00

debug.go

feat(coderd): add consolidated /debug/profile endpoint for pprof collection (#22892)

2026-03-13 14:09:39 +00:00

deployment_test.go

fix(coderd): mark provisioner daemon psk as secret (#12322)

2024-02-27 16:33:32 +00:00

deployment.go

chore: remove chats experiment (#18535)

2025-06-25 13:03:32 +00:00

deprecated.go

chore!: remove deprecated agent v1 routes (#13486)

2024-06-11 12:22:59 +10:00

exp_chats_test.go

feat: add deployment-wide template allowlist for chats (#23262)

2026-03-25 15:19:17 +00:00

exp_chats.go

perf(coderd/x/chatd): add process-wide config cache for hot DB queries (#23272)

2026-03-26 18:04:53 +11:00

experiments_test.go

chore: revert dynamic params as a safe experiment (#17510)

2025-04-22 16:21:15 +00:00

experiments.go

fix: do not warn on valid known experiments (#18514)

2025-06-24 09:14:41 +01:00

externalauth_test.go

feat(coderd/rbac): make organization-member a per-org system custom role (#21359)

2026-01-12 18:19:19 -08:00

externalauth.go

feat!: support PKCE in the oauth2 client's auth/exchange flow (#21215)

2025-12-15 17:41:47 +00:00

files_test.go

test: share coderdtest instances to stop paying the startup tax 22 times (#23454)

2026-03-23 19:54:43 +00:00

files.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

gitsshkey_test.go

chore: distinct operations for provisioner's 'parse', 'init', 'plan', 'apply', 'graph' (#21064)

2025-12-15 11:26:41 -06:00

gitsshkey.go

feat: add API key scope to restrict access to user data (#17692)

2025-05-15 15:32:52 +01:00

inboxnotifications_internal_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

inboxnotifications_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

inboxnotifications.go

fix(coderd): ensure inbox WebSocket is closed when client disconnects (#21652)

2026-01-26 09:24:45 +00:00

initscript_test.go

test: share coderdtest instances to stop paying the startup tax 22 times (#23454)

2026-03-23 19:54:43 +00:00

initscript.go

feat(coderd): add support for external agents to API's and provisioner (#19286)

2025-08-19 10:41:33 +02:00

insights_internal_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

insights_test.go

fix(coderd): fix flaky TestGetUserStatusCounts timezone boundary (#22639)

2026-03-04 18:01:56 -08:00

insights.go

fix: user status change chart accommodates DST (#22191)

2026-03-04 12:54:39 +02:00

latencycheck.go

…

mcp_http.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

mcp_test.go

fix(coderd): use path-aware discovery for MCP OAuth2 metadata (RFC 9728, RFC 8414) (#23520)

2026-03-25 14:35:55 -04:00

mcp.go

fix(coderd): use path-aware discovery for MCP OAuth2 metadata (RFC 9728, RFC 8414) (#23520)

2026-03-25 14:35:55 -04:00

members_test.go

feat: add filtering by service account (#23468)

2026-03-24 10:13:25 -08:00

members.go

feat: add filtering by service account (#23468)

2026-03-24 10:13:25 -08:00

notifications_test.go

chore: return 404, not 400 if missing or authz deny (#22069)

2026-02-13 08:19:07 -06:00

notifications.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

oauth2_error_compliance_test.go

test: reduce number of coderdtest instances (#23463)

2026-03-25 09:53:06 +00:00

oauth2_metadata_test.go

refactor: add RFC-compliant enum types and use SDK as source of truth (#21468)

2026-01-15 12:41:28 +03:00

oauth2_metadata_validation_test.go

test: share coderdtest instances in OAuth2 validation tests (#23455)

2026-03-23 21:03:34 +00:00

oauth2_security_test.go

test: reduce number of coderdtest instances (#23463)

2026-03-25 09:53:06 +00:00

oauth2_test.go

fix(coderd): use dbtime.Now() instead of time.Now() in test assertions against DB timestamps (#22685)

2026-03-06 09:14:11 +00:00

oauth2.go

feat: implement oauth2 RFC 7009 token revocation endpoint (#20362)

2025-10-22 15:18:42 -05:00

organizations_test.go

chore: protect organization endpoints with license (#14001)

2024-07-25 16:07:53 -05:00

organizations.go

chore(coderd/database): remove deprecated db2sdk.List(Lazy)? methods (#21902)

2026-02-03 17:52:07 +00:00

pagination_test.go

feat: add connectionlogs API (#18628)

2025-07-15 14:55:34 +10:00

pagination.go

feat: add connectionlogs API (#18628)

2025-07-15 14:55:34 +10:00

parameters_test.go

feat: archive modules in size order until limit is hit (#21773)

2026-02-02 09:03:18 -06:00

parameters.go

chore(coderd/database): remove deprecated db2sdk.List(Lazy)? methods (#21902)

2026-02-03 17:52:07 +00:00

presets_test.go

chore: remove unnecessary loop variable captures (#22180)

2026-02-19 09:02:19 +00:00

presets.go

feat: support icon and description in preset (#18977)

2025-07-28 15:02:26 +01:00

provisionerdaemons_test.go

feat: add filtering options to provisioners list (#19378)

2025-08-21 16:03:34 -04:00

provisionerdaemons.go

chore(coderd/database): remove deprecated db2sdk.List(Lazy)? methods (#21902)

2026-02-03 17:52:07 +00:00

provisionerjobs_internal_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

provisionerjobs_test.go

test: reduce unnecessary sleep durations in tests (#22552)

2026-03-03 10:19:00 -05:00

provisionerjobs.go

ci: bump the github-actions group across 1 directory with 9 updates (#23345)

2026-03-20 02:59:50 +00:00

roles_test.go

chore: protect organization endpoints with license (#14001)

2024-07-25 16:07:53 -05:00

roles.go

feat(coderd/rbac): make organization-member a per-org system custom role (#21359)

2026-01-12 18:19:19 -08:00

scopes_catalog_api_test.go

feat: add external API key scopes (#19916)

2025-09-26 11:43:32 +02:00

scopes_catalog.go

feat: add external API key scopes (#19916)

2025-09-26 11:43:32 +02:00

tailnet_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

tailnet.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

templates_test.go

fix(coderd): allow template deletion when only prebuild workspaces remain (#23417)

2026-03-25 09:43:06 +02:00

templates.go

fix(coderd): allow template deletion when only prebuild workspaces remain (#23417)

2026-03-25 09:43:06 +02:00

templateversions_test.go

test: share coderdtest instances to stop paying the startup tax 22 times (#23454)

2026-03-23 19:54:43 +00:00

templateversions.go

feat: validate prebuild presets using dynamic parameter validation (#21858)

2026-03-03 16:50:18 +00:00

updatecheck_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

updatecheck.go

…

userauth_test.go

test: reduce number of coderdtest instances (#23463)

2026-03-25 09:53:06 +00:00

userauth.go

refactor: replace sort.Strings with slices.Sort (#23457)

2026-03-23 23:19:23 +02:00

users_test.go

test: assert on user id, not entire user (#23632)

2026-03-25 19:09:25 +00:00

users.go

feat: add filtering by service account (#23468)

2026-03-24 10:13:25 -08:00

webpush_test.go

perf(coderd): reduce duplicated reads in push and webpush paths (#23115)

2026-03-17 13:50:47 +11:00

webpush.go

perf(coderd): reduce duplicated reads in push and webpush paths (#23115)

2026-03-17 13:50:47 +11:00

workspaceagentportshare_test.go

feat(coderd/rbac): make organization-member a per-org system custom role (#21359)

2026-01-12 18:19:19 -08:00

workspaceagentportshare.go

docs: fix swagger documentation for DELETE port share endpoint (#18426)

2025-06-18 14:07:53 +00:00

workspaceagents_internal_test.go

refactor: consolidate chat streaming endpoints under /stream (#23248)

2026-03-18 18:04:42 +00:00

workspaceagents_test.go

fix(coderd): use dbtime.Now() for tailnet telemetry timestamps (#22861)

2026-03-09 20:37:05 +00:00

workspaceagents.go

fix: limit calls to GetWorkspaceAgentByID in agentapi (#23015)

2026-03-20 15:42:05 -05:00

workspaceagentsrpc_internal_test.go

test: use not before in TestAgentConnectionMonitor_* (#21332)

2025-12-22 10:21:39 +04:00

workspaceagentsrpc_test.go

test: add testutil.WaitBuffer and replace time.Sleep in tests (#22922)

2026-03-12 18:07:52 +02:00

workspaceagentsrpc.go

fix: limit calls to GetWorkspaceAgentByID in agentapi (#23015)

2026-03-20 15:42:05 -05:00

workspaceapps_test.go

chore: remove unnecessary redeclarations in for loops (#18440)

2025-06-20 13:16:55 -06:00

workspaceapps.go

feat: add multi-scope support to API keys (#19917)

2025-09-26 11:56:34 +02:00

workspacebuilds_test.go

feat: add link for viewing raw build logs in workspace and template build jobs (#21727)

2026-02-03 09:45:23 +00:00

workspacebuilds.go

feat: add WatchAllWorkspaceBuilds endpoint for autostart scaletests (#22057)

2026-03-13 20:37:41 -07:00

workspaceproxies_test.go

fix: allow ports in wildcard url configuration (#11657)

2024-01-18 09:44:05 -06:00

workspaceproxies.go

feat: add MCP server configuration backend for chats (#23227)

2026-03-19 14:07:36 +00:00

workspaceresourceauth_test.go

chore: distinct operations for provisioner's 'parse', 'init', 'plan', 'apply', 'graph' (#21064)

2025-12-15 11:26:41 -06:00

workspaceresourceauth.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00

workspaces_scoped_test.go

chore: add permissions to coder:workspace.* scopes for functionality (#23515)

2026-03-25 13:46:58 -05:00

workspaces_test.go

test: remove classic params from ephemeral params test (#23302)

2026-03-19 11:32:36 -05:00

workspaces.go

fix: limit calls to GetWorkspaceAgentByID in agentapi (#23015)

2026-03-20 15:42:05 -05:00

workspaceupdates_test.go

chore: update testutil chan helpers (#17408)

2025-04-16 10:37:09 -06:00

workspaceupdates.go

chore: arrange imports in a standard way (#21452)

2026-01-08 15:24:11 +04:00