Tweak cache counters (#2575)

* Tweak cache counters

This makes the number of counters relative to the
maximum cache size. Since the counters
effectively manage the size of the bloom filter,
larger caches need more counters and smaller
caches need less.

10 counters per 1KB data means that the default
cache size of 1GB should result in a bloom filter
and TinyLRU admission set of about 16MB
estimated.

* Remove line left by accident
This commit is contained in:
Neil Alexander 2022-07-18 14:49:41 +01:00 committed by GitHub
parent a7e92f8cb9
commit 99b696e775
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@ -44,9 +44,9 @@ const (
func NewRistrettoCache(maxCost config.DataUnit, maxAge time.Duration, enablePrometheus bool) *Caches { func NewRistrettoCache(maxCost config.DataUnit, maxAge time.Duration, enablePrometheus bool) *Caches {
cache, err := ristretto.NewCache(&ristretto.Config{ cache, err := ristretto.NewCache(&ristretto.Config{
NumCounters: 1e5, // 10x number of expected cache items, affects bloom filter size, gives us room for 10,000 currently NumCounters: int64((maxCost / 1024) * 10), // 10 counters per 1KB data, affects bloom filter size
BufferItems: 64, // recommended by the ristretto godocs as a sane buffer size value BufferItems: 64, // recommended by the ristretto godocs as a sane buffer size value
MaxCost: int64(maxCost), MaxCost: int64(maxCost), // max cost is in bytes, as per the Dendrite config
Metrics: true, Metrics: true,
KeyToHash: func(key interface{}) (uint64, uint64) { KeyToHash: func(key interface{}) (uint64, uint64) {
return z.KeyToHash(key) return z.KeyToHash(key)