prysm-pulse/slasher/cache/flat_span_cache.go
Marcin Górzyński 02966e64d8
Feature lru cache wrapper 2 (#9511)
* Add Wrapper to LRU Cache to handle Invalid Parameters #9461

* Regenerate BUILD.bazel and simplify tests using lru.Cache

* Fix: fuzz_exports.go build error

* Fix: block_fuzz.go

* Revert lru.Cache interface

* Remove redundant err check in pending_attestations_queue_test.go

* Add tests for lru wrapper

* Use lru package in prysm/shared instead of lruwrpr

* Fix: goimports

* Fix: BUILD.bazel

Co-authored-by: Nishant Das <nishdas93@gmail.com>
2021-09-02 18:36:54 +08:00

70 lines
2.2 KiB
Go

package cache
import (
lru "github.com/hashicorp/golang-lru"
types "github.com/prysmaticlabs/eth2-types"
lruwrpr "github.com/prysmaticlabs/prysm/shared/lru"
slashertypes "github.com/prysmaticlabs/prysm/slasher/detection/attestations/types"
)
// EpochFlatSpansCache is used to store the spans needed on a per-epoch basis for slashing detection.
type EpochFlatSpansCache struct {
cache *lru.Cache
}
// NewEpochFlatSpansCache initializes the underlying cache with the given size and on evict function.
func NewEpochFlatSpansCache(size int, onEvicted func(key interface{}, value interface{})) (*EpochFlatSpansCache, error) {
if size != 0 {
epochSpansCacheSize = size
}
return &EpochFlatSpansCache{cache: lruwrpr.NewWithEvict(epochSpansCacheSize, onEvicted)}, nil
}
// Get returns an ok bool and the cached value for the requested epoch key, if any.
func (c *EpochFlatSpansCache) Get(epoch types.Epoch) (*slashertypes.EpochStore, bool) {
item, exists := c.cache.Get(epoch)
if exists && item != nil {
epochSpansCacheHit.Inc()
return item.(*slashertypes.EpochStore), true
}
epochSpansCacheMiss.Inc()
return &slashertypes.EpochStore{}, false
}
// Set the response in the cache.
func (c *EpochFlatSpansCache) Set(epoch types.Epoch, epochSpans *slashertypes.EpochStore) {
_ = c.cache.Add(epoch, epochSpans)
}
// Delete removes an epoch from the cache and returns if it existed or not.
// Performs the onEviction function before removal.
func (c *EpochFlatSpansCache) Delete(epoch types.Epoch) bool {
return c.cache.Remove(epoch)
}
// PruneOldest removes the oldest key from the span cache, calling its OnEvict function.
func (c *EpochFlatSpansCache) PruneOldest() uint64 {
if c.cache.Len() == epochSpansCacheSize {
epoch, _, _ := c.cache.RemoveOldest()
return epoch.(uint64)
}
return 0
}
// Has returns true if the key exists in the cache.
func (c *EpochFlatSpansCache) Has(epoch types.Epoch) bool {
return c.cache.Contains(epoch)
}
// Purge removes all keys from the SpanCache and evicts all current data.
func (c *EpochFlatSpansCache) Purge() {
log.Info("Saving all cached data to DB, please wait for completion.")
c.cache.Purge()
}
// Length returns the number of cached items.
func (c *EpochFlatSpansCache) Length() int {
return c.cache.Len()
}