distribution/docs/storage/blobcachemetrics.go
Derek McGowan 568df315ff Open cache interface
Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
2015-05-15 17:56:28 -07:00

61 lines
1.6 KiB
Go

package storage
import (
"expvar"
"sync/atomic"
"github.com/docker/distribution/registry/storage/cache"
)
type blobStatCollector struct {
metrics cache.Metrics
}
func (bsc *blobStatCollector) Hit() {
atomic.AddUint64(&bsc.metrics.Requests, 1)
atomic.AddUint64(&bsc.metrics.Hits, 1)
}
func (bsc *blobStatCollector) Miss() {
atomic.AddUint64(&bsc.metrics.Requests, 1)
atomic.AddUint64(&bsc.metrics.Misses, 1)
}
func (bsc *blobStatCollector) Metrics() cache.Metrics {
return bsc.metrics
}
// blobStatterCacheMetrics keeps track of cache metrics for blob descriptor
// cache requests. Note this is kept globally and made available via expvar.
// For more detailed metrics, its recommend to instrument a particular cache
// implementation.
var blobStatterCacheMetrics cache.MetricsTracker = &blobStatCollector{}
func init() {
registry := expvar.Get("registry")
if registry == nil {
registry = expvar.NewMap("registry")
}
cache := registry.(*expvar.Map).Get("cache")
if cache == nil {
cache = &expvar.Map{}
cache.(*expvar.Map).Init()
registry.(*expvar.Map).Set("cache", cache)
}
storage := cache.(*expvar.Map).Get("storage")
if storage == nil {
storage = &expvar.Map{}
storage.(*expvar.Map).Init()
cache.(*expvar.Map).Set("storage", storage)
}
storage.(*expvar.Map).Set("blobdescriptor", expvar.Func(func() interface{} {
// no need for synchronous access: the increments are atomic and
// during reading, we don't care if the data is up to date. The
// numbers will always *eventually* be reported correctly.
return blobStatterCacheMetrics
}))
}