(chore): remove incorrect cache config preample (#8859)

With the addition of the [config generation tool](https://github.com/grafana/loki/pull/7916), a comment prefix was added for all cache types: `Cache config for index entry writing.` https://grafana.com/docs/loki/next/configuration/#cache_config This appears in the description of each cache config option, and is misleading.
2 years ago · 2d93952929
parent ee371a867d
commit 2d93952929
3 changed files with 54 additions and 75 deletions
--- a/docs/sources/configuration/_index.md
+++ b/docs/sources/configuration/_index.md
@ -3388,196 +3388,175 @@ The cache block configures the cache backend. The supported CLI flags `<prefix>`
 &nbsp;

 ```yaml
-# Cache config for index entry writing.(deprecated: use embedded-cache instead)
-# Enable in-memory cache (auto-enabled for the chunks & query results cache if
-# no other cache is configured).
+# (deprecated: use embedded-cache instead) Enable in-memory cache (auto-enabled
+# for the chunks & query results cache if no other cache is configured).
 # CLI flag: -<prefix>.cache.enable-fifocache
 [enable_fifocache: <boolean> | default = false]

-# Cache config for index entry writing.The default validity of entries for
-# caches unless overridden.
+# The default validity of entries for caches unless overridden.
 # CLI flag: -<prefix>.default-validity
 [default_validity: <duration> | default = 1h]

 background:
-  # Cache config for index entry writing.At what concurrency to write back to
-  # cache.
+  # At what concurrency to write back to cache.
  # CLI flag: -<prefix>.background.write-back-concurrency
  [writeback_goroutines: <int> | default = 10]

-  # Cache config for index entry writing.How many key batches to buffer for
-  # background write-back.
+  # How many key batches to buffer for background write-back.
  # CLI flag: -<prefix>.background.write-back-buffer
  [writeback_buffer: <int> | default = 10000]

 memcached:
-  # Cache config for index entry writing.How long keys stay in the memcache.
+  # How long keys stay in the memcache.
  # CLI flag: -<prefix>.memcached.expiration
  [expiration: <duration> | default = 0s]

-  # Cache config for index entry writing.How many keys to fetch in each batch.
+  # How many keys to fetch in each batch.
  # CLI flag: -<prefix>.memcached.batchsize
  [batch_size: <int> | default = 1024]

-  # Cache config for index entry writing.Maximum active requests to memcache.
+  # Maximum active requests to memcache.
  # CLI flag: -<prefix>.memcached.parallelism
  [parallelism: <int> | default = 100]

 memcached_client:
-  # Cache config for index entry writing.Hostname for memcached service to use.
-  # If empty and if addresses is unset, no memcached will be used.
+  # Hostname for memcached service to use. If empty and if addresses is unset,
+  # no memcached will be used.
  # CLI flag: -<prefix>.memcached.hostname
  [host: <string> | default = ""]

-  # Cache config for index entry writing.SRV service used to discover memcache
-  # servers.
+  # SRV service used to discover memcache servers.
  # CLI flag: -<prefix>.memcached.service
  [service: <string> | default = "memcached"]

-  # Cache config for index entry writing.EXPERIMENTAL: Comma separated addresses
-  # list in DNS Service Discovery format:
+  # EXPERIMENTAL: Comma separated addresses list in DNS Service Discovery
+  # format:
  # https://cortexmetrics.io/docs/configuration/arguments/#dns-service-discovery
  # CLI flag: -<prefix>.memcached.addresses
  [addresses: <string> | default = ""]

-  # Cache config for index entry writing.Maximum time to wait before giving up
-  # on memcached requests.
+  # Maximum time to wait before giving up on memcached requests.
  # CLI flag: -<prefix>.memcached.timeout
  [timeout: <duration> | default = 100ms]

-  # Cache config for index entry writing.Maximum number of idle connections in
-  # pool.
+  # Maximum number of idle connections in pool.
  # CLI flag: -<prefix>.memcached.max-idle-conns
  [max_idle_conns: <int> | default = 16]

-  # Cache config for index entry writing.The maximum size of an item stored in
-  # memcached. Bigger items are not stored. If set to 0, no maximum size is
-  # enforced.
+  # The maximum size of an item stored in memcached. Bigger items are not
+  # stored. If set to 0, no maximum size is enforced.
  # CLI flag: -<prefix>.memcached.max-item-size
  [max_item_size: <int> | default = 0]

-  # Cache config for index entry writing.Period with which to poll DNS for
-  # memcache servers.
+  # Period with which to poll DNS for memcache servers.
  # CLI flag: -<prefix>.memcached.update-interval
  [update_interval: <duration> | default = 1m]

-  # Cache config for index entry writing.Use consistent hashing to distribute to
-  # memcache servers.
+  # Use consistent hashing to distribute to memcache servers.
  # CLI flag: -<prefix>.memcached.consistent-hash
  [consistent_hash: <boolean> | default = true]

-  # Cache config for index entry writing.Trip circuit-breaker after this number
-  # of consecutive dial failures (if zero then circuit-breaker is disabled).
+  # Trip circuit-breaker after this number of consecutive dial failures (if zero
+  # then circuit-breaker is disabled).
  # CLI flag: -<prefix>.memcached.circuit-breaker-consecutive-failures
  [circuit_breaker_consecutive_failures: <int> | default = 10]

-  # Cache config for index entry writing.Duration circuit-breaker remains open
-  # after tripping (if zero then 60 seconds is used).
+  # Duration circuit-breaker remains open after tripping (if zero then 60
+  # seconds is used).
  # CLI flag: -<prefix>.memcached.circuit-breaker-timeout
  [circuit_breaker_timeout: <duration> | default = 10s]

-  # Cache config for index entry writing.Reset circuit-breaker counts after this
-  # long (if zero then never reset).
+  # Reset circuit-breaker counts after this long (if zero then never reset).
  # CLI flag: -<prefix>.memcached.circuit-breaker-interval
  [circuit_breaker_interval: <duration> | default = 10s]

 redis:
-  # Cache config for index entry writing.Redis Server or Cluster configuration
-  # endpoint to use for caching. A comma-separated list of endpoints for Redis
-  # Cluster or Redis Sentinel. If empty, no redis will be used.
+  # Redis Server or Cluster configuration endpoint to use for caching. A
+  # comma-separated list of endpoints for Redis Cluster or Redis Sentinel. If
+  # empty, no redis will be used.
  # CLI flag: -<prefix>.redis.endpoint
  [endpoint: <string> | default = ""]

-  # Cache config for index entry writing.Redis Sentinel master name. An empty
-  # string for Redis Server or Redis Cluster.
+  # Redis Sentinel master name. An empty string for Redis Server or Redis
+  # Cluster.
  # CLI flag: -<prefix>.redis.master-name
  [master_name: <string> | default = ""]

-  # Cache config for index entry writing.Maximum time to wait before giving up
-  # on redis requests.
+  # Maximum time to wait before giving up on redis requests.
  # CLI flag: -<prefix>.redis.timeout
  [timeout: <duration> | default = 500ms]

-  # Cache config for index entry writing.How long keys stay in the redis.
+  # How long keys stay in the redis.
  # CLI flag: -<prefix>.redis.expiration
  [expiration: <duration> | default = 0s]

-  # Cache config for index entry writing.Database index.
+  # Database index.
  # CLI flag: -<prefix>.redis.db
  [db: <int> | default = 0]

-  # Cache config for index entry writing.Maximum number of connections in the
-  # pool.
+  # Maximum number of connections in the pool.
  # CLI flag: -<prefix>.redis.pool-size
  [pool_size: <int> | default = 0]

-  # Cache config for index entry writing.Username to use when connecting to
-  # redis.
+  # Username to use when connecting to redis.
  # CLI flag: -<prefix>.redis.username
  [username: <string> | default = ""]

-  # Cache config for index entry writing.Password to use when connecting to
-  # redis.
+  # Password to use when connecting to redis.
  # CLI flag: -<prefix>.redis.password
  [password: <string> | default = ""]

-  # Cache config for index entry writing.Enable connecting to redis with TLS.
+  # Enable connecting to redis with TLS.
  # CLI flag: -<prefix>.redis.tls-enabled
  [tls_enabled: <boolean> | default = false]

-  # Cache config for index entry writing.Skip validating server certificate.
+  # Skip validating server certificate.
  # CLI flag: -<prefix>.redis.tls-insecure-skip-verify
  [tls_insecure_skip_verify: <boolean> | default = false]

-  # Cache config for index entry writing.Close connections after remaining idle
-  # for this duration. If the value is zero, then idle connections are not
-  # closed.
+  # Close connections after remaining idle for this duration. If the value is
+  # zero, then idle connections are not closed.
  # CLI flag: -<prefix>.redis.idle-timeout
  [idle_timeout: <duration> | default = 0s]

-  # Cache config for index entry writing.Close connections older than this
-  # duration. If the value is zero, then the pool does not close connections
-  # based on age.
+  # Close connections older than this duration. If the value is zero, then the
+  # pool does not close connections based on age.
  # CLI flag: -<prefix>.redis.max-connection-age
  [max_connection_age: <duration> | default = 0s]

 embedded_cache:
-  # Cache config for index entry writing.Whether embedded cache is enabled.
+  # Whether embedded cache is enabled.
  # CLI flag: -<prefix>.embedded-cache.enabled
  [enabled: <boolean> | default = false]

-  # Cache config for index entry writing.Maximum memory size of the cache in MB.
+  # Maximum memory size of the cache in MB.
  # CLI flag: -<prefix>.embedded-cache.max-size-mb
  [max_size_mb: <int> | default = 100]

-  # Cache config for index entry writing.The time to live for items in the cache
-  # before they get purged.
+  # The time to live for items in the cache before they get purged.
  # CLI flag: -<prefix>.embedded-cache.ttl
  [ttl: <duration> | default = 1h]

 fifocache:
-  # Cache config for index entry writing.Maximum memory size of the cache in
-  # bytes. A unit suffix (KB, MB, GB) may be applied.
+  # Maximum memory size of the cache in bytes. A unit suffix (KB, MB, GB) may be
+  # applied.
  # CLI flag: -<prefix>.fifocache.max-size-bytes
  [max_size_bytes: <string> | default = "1GB"]

-  # Cache config for index entry writing.deprecated: Maximum number of entries
-  # in the cache.
+  # deprecated: Maximum number of entries in the cache.
  # CLI flag: -<prefix>.fifocache.max-size-items
  [max_size_items: <int> | default = 0]

-  # Cache config for index entry writing.The time to live for items in the cache
-  # before they get purged.
+  # The time to live for items in the cache before they get purged.
  # CLI flag: -<prefix>.fifocache.ttl
  [ttl: <duration> | default = 1h]

-  # Deprecated (use ttl instead): Cache config for index entry writing.The
-  # expiry duration for the cache.
+  # Deprecated (use ttl instead): The expiry duration for the cache.
  # CLI flag: -<prefix>.fifocache.duration
  [validity: <duration> | default = 0s]

-  # Deprecated (use max-size-items or max-size-bytes instead): Cache config for
-  # index entry writing.The number of entries to cache.
+  # Deprecated (use max-size-items or max-size-bytes instead): The number of
+  # entries to cache.
  # CLI flag: -<prefix>.fifocache.size
  [size: <int> | default = 0]

--- a/pkg/storage/config/store.go
+++ b/pkg/storage/config/store.go
@ -37,9 +37,9 @@ func (cfg *ChunkStoreConfig) ChunkCacheStubs() bool {

 // RegisterFlags adds the flags required to configure this flag set.
 func (cfg *ChunkStoreConfig) RegisterFlags(f *flag.FlagSet) {
-	cfg.ChunkCacheConfig.RegisterFlagsWithPrefix("store.chunks-cache.", "Cache config for chunks. ", f)
+	cfg.ChunkCacheConfig.RegisterFlagsWithPrefix("store.chunks-cache.", "", f)
 	f.BoolVar(&cfg.chunkCacheStubs, "store.chunks-cache.cache-stubs", false, "If true, don't write the full chunk to cache, just a stub entry.")
-	cfg.WriteDedupeCacheConfig.RegisterFlagsWithPrefix("store.index-cache-write.", "Cache config for index entry writing.", f)
+	cfg.WriteDedupeCacheConfig.RegisterFlagsWithPrefix("store.index-cache-write.", "", f)

 	f.Var(&cfg.CacheLookupsOlderThan, "store.cache-lookups-older-than", "Cache index entries older than this period. 0 to disable.")
 	f.Var(&cfg.MaxLookBackPeriod, "store.max-look-back-period", "This flag is deprecated. Use -querier.max-query-lookback instead.")
--- a/pkg/storage/factory.go
+++ b/pkg/storage/factory.go
@ -209,7 +209,7 @@ func (cfg *Config) RegisterFlags(f *flag.FlagSet) {
 	cfg.GrpcConfig.RegisterFlags(f)
 	cfg.Hedging.RegisterFlagsWithPrefix("store.", f)

-	cfg.IndexQueriesCacheConfig.RegisterFlagsWithPrefix("store.index-cache-read.", "Cache config for index entry reading.", f)
+	cfg.IndexQueriesCacheConfig.RegisterFlagsWithPrefix("store.index-cache-read.", "", f)
 	f.DurationVar(&cfg.IndexCacheValidity, "store.index-cache-validity", 5*time.Minute, "Cache validity for active index entries. Should be no higher than -ingester.max-chunk-idle.")
 	f.BoolVar(&cfg.DisableBroadIndexQueries, "store.disable-broad-index-queries", false, "Disable broad index queries which results in reduced cache usage and faster query performance at the expense of somewhat higher QPS on the index store.")
 	f.IntVar(&cfg.MaxParallelGetChunk, "store.max-parallel-get-chunk", 150, "Maximum number of parallel chunk reads.")