Tweak max age handling, config key name

dendrite-sample.monolith.yaml

@@ -41,15 +41,16 @@ global:
     max_idle_conns: 5
     conn_max_lifetime: -1
 
-  # Configuration for in-process caches, to help speed up processing transactions
-  # and reducing load on the database.
+  # Configuration for in-memory caches. Caches can often improve performance by
+  # keeping frequently accessed items (like events, identifiers etc.) in memory
+  # rather than having to read them from the database.
   cache:
     # The estimated maximum size for the global cache in bytes, or in terabytes,
     # gigabytes, megabytes or kilobytes when the appropriate 'tb', 'gb', 'mb' or
     # 'kb' suffix is specified. Note that this is not a hard limit, nor is it a
     # memory limit for the entire process. A cache that is too small may ultimately
     # provide little or no benefit.
-    max_bytes_est: 1gb
+    max_size_est: 1gb
 
     # The maximum amount of time that a cache entry can live for in memory before
     # it will be evicted and/or refreshed from the database. Lower values result in

dendrite-sample.polylith.yaml

@@ -31,15 +31,16 @@ global:
   # considered valid by other homeservers.
   key_validity_period: 168h0m0s
 
-  # Configuration for in-process caches, to help speed up processing transactions
-  # and reducing load on the database.
+  # Configuration for in-memory caches. Caches can often improve performance by
+  # keeping frequently accessed items (like events, identifiers etc.) in memory
+  # rather than having to read them from the database.
   cache:
     # The estimated maximum size for the global cache in bytes, or in terabytes,
     # gigabytes, megabytes or kilobytes when the appropriate 'tb', 'gb', 'mb' or
     # 'kb' suffix is specified. Note that this is not a hard limit, nor is it a
     # memory limit for the entire process. A cache that is too small may ultimately
     # provide little or no benefit.
-    max_bytes_est: 1gb
+    max_size_est: 1gb
 
     # The maximum amount of time that a cache entry can live for in memory before
     # it will be evicted and/or refreshed from the database. Lower values result in

internal/caching/impl_ristretto.go

@@ -94,7 +94,7 @@ func NewRistrettoCache(maxCost config.DataUnit, maxAge time.Duration, enableProm
 				cache:   cache,
 				Prefix:  federationPDUsCache,
 				Mutable: true,
-				MaxAge:  time.Hour / 2,
+				MaxAge:  lesserOf(time.Hour/2, maxAge),
 			},
 		},
 		FederationEDUs: &RistrettoCostedCachePartition[int64, *gomatrixserverlib.EDU]{
@@ -102,7 +102,7 @@ func NewRistrettoCache(maxCost config.DataUnit, maxAge time.Duration, enableProm
 				cache:   cache,
 				Prefix:  federationEDUsCache,
 				Mutable: true,
-				MaxAge:  time.Hour / 2,
+				MaxAge:  lesserOf(time.Hour/2, maxAge),
 			},
 		},
 		SpaceSummaryRooms: &RistrettoCachePartition[string, gomatrixserverlib.MSC2946SpacesResponse]{
@@ -174,3 +174,10 @@ func (c *RistrettoCachePartition[K, V]) Get(key K) (value V, ok bool) {
 	value, ok = v.(V)
 	return
 }
+
+func lesserOf(a, b time.Duration) time.Duration {
+	if a < b {
+		return a
+	}
+	return b
+}

setup/config/config_global.go

@@ -176,7 +176,7 @@ func (c *ServerNotices) Defaults(generate bool) {
 func (c *ServerNotices) Verify(errors *ConfigErrors, isMonolith bool) {}
 
 type Cache struct {
-	EstMaxSize DataUnit      `yaml:"max_bytes_est"`
+	EstMaxSize DataUnit      `yaml:"max_size_est"`
 	MaxAge     time.Duration `yaml:"max_age"`
 }
 
@@ -186,7 +186,7 @@ func (c *Cache) Defaults(generate bool) {
 }
 
 func (c *Cache) Verify(errors *ConfigErrors, isMonolith bool) {
-	checkPositive(errors, "max_bytes_est", int64(c.EstMaxSize))
+	checkPositive(errors, "max_size_est", int64(c.EstMaxSize))
 }
 
 // ReportStats configures opt-in anonymous stats reporting.