walcache

Documentation

Index

• type WALCache
  • func New(ctx context.Context, cfg *config.Config, metrics *cgm.CirconusMetrics, ...) (*WALCache, error)
  • func (wc *WALCache) Get(k interface{}) (interface{}, error)
  • func (wc *WALCache) GetIFPresent(k interface{}) (interface{}, error)
  • func (wc *WALCache) Purge()
  • func (wc *WALCache) ReadAhead() uint32
  • func (wc *WALCache) Wait()

Types

type WALCache

type WALCache struct {
	// contains filtered or unexported fields
}

WALCache is a read-through cache to:

a) provide a reentrant interface b) deduplicate requests (i.e. no thundering-herd for the same WAL file) c) deliberately intollerant of scans because we know the input is monotonic d) sized to include only the walReadAhead

func New

func New(ctx context.Context, cfg *config.Config, metrics *cgm.CirconusMetrics, ioCache *iocache.IOCache) (*WALCache, error)

func (*WALCache) Get

func (wc *WALCache) Get(k interface{}) (interface{}, error)

Get forwards to gcache.Cache's Get().

func (*WALCache) GetIFPresent

func (wc *WALCache) GetIFPresent(k interface{}) (interface{}, error)

GetIFPresent forwards to gcache.Cache's GetIFPresent().

func (*WALCache) Purge

func (wc *WALCache) Purge()

Purge purges the WALCache of its cache (and all downstream caches)

func (*WALCache) ReadAhead

func (wc *WALCache) ReadAhead() uint32

ReadAhead returns the number of WAL files to read ahead of PostgreSQL.

func (*WALCache) Wait

func (wc *WALCache) Wait()

Wait blocks until the WALCache finishes shutting down its workers (including the workers of its IOCache).