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

3 files changed, 68 insertions, 6 deletions

diff --git a/setup/base/base.go b/setup/base/base.go
index 5cbd7da9..93ab87de 100644
--- a/setup/base/base.go
+++ b/setup/base/base.go
@@ -161,11 +161,6 @@ func NewBaseDendrite(cfg *config.Dendrite, componentName string, options ...Base
 		}
 	}
 
-	cache, err := caching.NewInMemoryLRUCache(enableMetrics)
-	if err != nil {
-		logrus.WithError(err).Warnf("Failed to create cache")
-	}
-
 	var dnsCache *gomatrixserverlib.DNSCache
 	if cfg.Global.DNSCache.Enabled {
 		dnsCache = gomatrixserverlib.NewDNSCache(
@@ -233,7 +228,7 @@ func NewBaseDendrite(cfg *config.Dendrite, componentName string, options ...Base
 		UseHTTPAPIs:            useHTTPAPIs,
 		tracerCloser:           closer,
 		Cfg:                    cfg,
-		Caches:                 cache,
+		Caches:                 caching.NewRistrettoCache(cfg.Global.Cache.EstimatedMaxSize, cfg.Global.Cache.MaxAge, enableMetrics),
 		DNSCache:               dnsCache,
 		PublicClientAPIMux:     mux.NewRouter().SkipClean(true).PathPrefix(httputil.PublicClientPathPrefix).Subrouter().UseEncodedPath(),
 		PublicFederationAPIMux: mux.NewRouter().SkipClean(true).PathPrefix(httputil.PublicFederationPathPrefix).Subrouter().UseEncodedPath(),
diff --git a/setup/config/config_global.go b/setup/config/config_global.go
index 9d4c1485..ac1380a4 100644
--- a/setup/config/config_global.go
+++ b/setup/config/config_global.go
@@ -2,6 +2,8 @@ package config
 
 import (
 	"math/rand"
+	"strconv"
+	"strings"
 	"time"
 
 	"github.com/matrix-org/gomatrixserverlib"
@@ -73,6 +75,9 @@ type Global struct {
 
 	// ReportStats configures opt-in anonymous stats reporting.
 	ReportStats ReportStats `yaml:"report_stats"`
+
+	// Configuration for the caches.
+	Cache Cache `yaml:"cache"`
 }
 
 func (c *Global) Defaults(generate bool) {
@@ -90,6 +95,7 @@ func (c *Global) Defaults(generate bool) {
 	c.Sentry.Defaults()
 	c.ServerNotices.Defaults(generate)
 	c.ReportStats.Defaults()
+	c.Cache.Defaults(generate)
 }
 
 func (c *Global) Verify(configErrs *ConfigErrors, isMonolith bool) {
@@ -102,6 +108,7 @@ func (c *Global) Verify(configErrs *ConfigErrors, isMonolith bool) {
 	c.DNSCache.Verify(configErrs, isMonolith)
 	c.ServerNotices.Verify(configErrs, isMonolith)
 	c.ReportStats.Verify(configErrs, isMonolith)
+	c.Cache.Verify(configErrs, isMonolith)
 }
 
 type OldVerifyKeys struct {
@@ -168,6 +175,20 @@ func (c *ServerNotices) Defaults(generate bool) {
 
 func (c *ServerNotices) Verify(errors *ConfigErrors, isMonolith bool) {}
 
+type Cache struct {
+	EstimatedMaxSize DataUnit      `yaml:"max_size_estimated"`
+	MaxAge           time.Duration `yaml:"max_age"`
+}
+
+func (c *Cache) Defaults(generate bool) {
+	c.EstimatedMaxSize = 1024 * 1024 * 1024 // 1GB
+	c.MaxAge = time.Hour
+}
+
+func (c *Cache) Verify(errors *ConfigErrors, isMonolith bool) {
+	checkPositive(errors, "max_size_estimated", int64(c.EstimatedMaxSize))
+}
+
 // ReportStats configures opt-in anonymous stats reporting.
 type ReportStats struct {
 	// Enabled configures anonymous usage stats of the server
@@ -268,3 +289,28 @@ type PresenceOptions struct {
 	// Whether outbound presence events are allowed
 	EnableOutbound bool `yaml:"enable_outbound"`
 }
+
+type DataUnit int64
+
+func (d *DataUnit) UnmarshalText(text []byte) error {
+	var magnitude float64
+	s := strings.ToLower(string(text))
+	switch {
+	case strings.HasSuffix(s, "tb"):
+		s, magnitude = s[:len(s)-2], 1024*1024*1024*1024
+	case strings.HasSuffix(s, "gb"):
+		s, magnitude = s[:len(s)-2], 1024*1024*1024
+	case strings.HasSuffix(s, "mb"):
+		s, magnitude = s[:len(s)-2], 1024*1024
+	case strings.HasSuffix(s, "kb"):
+		s, magnitude = s[:len(s)-2], 1024
+	default:
+		magnitude = 1
+	}
+	v, err := strconv.ParseFloat(s, 64)
+	if err != nil {
+		return err
+	}
+	*d = DataUnit(v * magnitude)
+	return nil
+}
diff --git a/setup/config/config_test.go b/setup/config/config_test.go
index cbc57ad1..b9b1e7bb 100644
--- a/setup/config/config_test.go
+++ b/setup/config/config_test.go
@@ -17,6 +17,8 @@ package config
 import (
 	"fmt"
 	"testing"
+
+	"gopkg.in/yaml.v2"
 )
 
 func TestLoadConfigRelative(t *testing.T) {
@@ -268,3 +270,22 @@ n0Xq64k7fc42HXJpF8CGBkSaIhtlzcruO+vqR80B9r62+D0V7VmHOnP135MT6noU
 ANAf5kxmMsM0zlN2hkxl0H6o7wKlBSw3RI3cjfilXiMWRPJrzlc4
 -----END CERTIFICATE-----
 `
+
+func TestUnmarshalDataUnit(t *testing.T) {
+	target := struct {
+		Got DataUnit `yaml:"value"`
+	}{}
+	for input, expect := range map[string]DataUnit{
+		"value: 0.6tb": 659706976665,
+		"value: 1.2gb": 1288490188,
+		"value: 256mb": 268435456,
+		"value: 128kb": 131072,
+		"value: 128":   128,
+	} {
+		if err := yaml.Unmarshal([]byte(input), &target); err != nil {
+			t.Fatal(err)
+		} else if target.Got != expect {
+			t.Fatalf("expected value %d but got %d", expect, target.Got)
+		}
+	}
+}