Ristretto cache (#2563)

* Try Ristretto cache

* Tweak

* It's beautiful

* Update GMSL

* More strict keyable interface

* Fix that some more

* Make less panicky

* Don't enforce mutability checks for now

* Determine mutability using deep equality

* Tweaks

* Namespace keys

* Make federation caches mutable

* Update cost estimation, add metric

* Update GMSL

* Estimate cost for metrics better

* Reduce counters a bit

* Try caching events

* Some guards

* Try again

* Try this

* Use separate caches for hopefully better hash distribution

* Fix bug with admitting events into cache

* Try to fix bugs

* Check nil

* Try that again

* Preserve order jeezo this is messy

* thanks VS Code for doing exactly the wrong thing

* Try this again

* Be more specific

* aaaaargh

* One more time

* That might be better

* Stronger sorting

* Cache expiries, async publishing of EDUs

* Put it back

* Use a shared cache again

* Cost estimation fixes

* Update ristretto

* Reduce counters a bit

* Clean up a bit

* Update GMSL

* 1GB

* Configurable cache sizees

* Tweaks

* Add `config.DataUnit` for specifying friendly cache sizes

* Various tweaks

* Update GMSL

* Add back some lazy loading caching

* Include key in cost

* Include key in cost

* Tweak max age handling, config key name

* Only register prometheus metrics if requested

* Review comments @S7evinK

* Don't return errors when creating caches (it is better just to crash since otherwise we'll `nil`-pointer exception everywhere)

* Review comments

* Update sample configs

* Update GHA Workflow

* Update Complement images to Go 1.18

* Remove the cache test from the federation API as we no longer guarantee immediate cache admission

* Don't check the caches in the renewal test

* Possibly fix the upgrade tests

* Update to matrix-org/gomatrixserverlib#322

* Update documentation to refer to Go 1.18

1 files changed, 6 insertions, 33 deletions

diff --git a/internal/caching/cache_federationevents.go b/internal/caching/cache_federationevents.go
index b79cc809..24af51bd 100644
--- a/internal/caching/cache_federationevents.go
+++ b/internal/caching/cache_federationevents.go
@@ -1,18 +1,9 @@
 package caching
 
 import (
-	"fmt"
-
 	"github.com/matrix-org/gomatrixserverlib"
 )
 
-const (
-	FederationEventCacheName       = "federation_event"
-	FederationEventCacheMaxEntries = 256
-	FederationEventCacheMutable    = true // to allow use of Unset only
-	FederationEventCacheMaxAge     = CacheNoMaxAge
-)
-
 // FederationCache contains the subset of functions needed for
 // a federation event cache.
 type FederationCache interface {
@@ -26,43 +17,25 @@ type FederationCache interface {
 }
 
 func (c Caches) GetFederationQueuedPDU(eventNID int64) (*gomatrixserverlib.HeaderedEvent, bool) {
-	key := fmt.Sprintf("%d", eventNID)
-	val, found := c.FederationEvents.Get(key)
-	if found && val != nil {
-		if event, ok := val.(*gomatrixserverlib.HeaderedEvent); ok {
-			return event, true
-		}
-	}
-	return nil, false
+	return c.FederationPDUs.Get(eventNID)
 }
 
 func (c Caches) StoreFederationQueuedPDU(eventNID int64, event *gomatrixserverlib.HeaderedEvent) {
-	key := fmt.Sprintf("%d", eventNID)
-	c.FederationEvents.Set(key, event)
+	c.FederationPDUs.Set(eventNID, event)
 }
 
 func (c Caches) EvictFederationQueuedPDU(eventNID int64) {
-	key := fmt.Sprintf("%d", eventNID)
-	c.FederationEvents.Unset(key)
+	c.FederationPDUs.Unset(eventNID)
 }
 
 func (c Caches) GetFederationQueuedEDU(eventNID int64) (*gomatrixserverlib.EDU, bool) {
-	key := fmt.Sprintf("%d", eventNID)
-	val, found := c.FederationEvents.Get(key)
-	if found && val != nil {
-		if event, ok := val.(*gomatrixserverlib.EDU); ok {
-			return event, true
-		}
-	}
-	return nil, false
+	return c.FederationEDUs.Get(eventNID)
 }
 
 func (c Caches) StoreFederationQueuedEDU(eventNID int64, event *gomatrixserverlib.EDU) {
-	key := fmt.Sprintf("%d", eventNID)
-	c.FederationEvents.Set(key, event)
+	c.FederationEDUs.Set(eventNID, event)
 }
 
 func (c Caches) EvictFederationQueuedEDU(eventNID int64) {
-	key := fmt.Sprintf("%d", eventNID)
-	c.FederationEvents.Unset(key)
+	c.FederationEDUs.Unset(eventNID)
 }