frostfs-node/cmd/neofs-node/cache.go
Alex Vanin 518f375dfd [] cmd/neofs-node: Don't update access time in ttlNetCache
ttlNetCache should evict records after TTL duration. However if
data is often accessed and there are no LRU eviction (cache used
with small number of keys), then data will not be evicted ever.

This is a invalid behaviour for mutable data such as eACL.

Solution is to not update access time on every get, so the data
will be guarantee evicted after TTL duration.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2021-03-23 20:19:16 +03:00

228 lines
4.6 KiB
Go

package main
import (
"sync"
"time"
lru "github.com/hashicorp/golang-lru"
eaclSDK "github.com/nspcc-dev/neofs-api-go/pkg/acl/eacl"
containerSDK "github.com/nspcc-dev/neofs-api-go/pkg/container"
netmapSDK "github.com/nspcc-dev/neofs-api-go/pkg/netmap"
"github.com/nspcc-dev/neofs-node/pkg/core/container"
"github.com/nspcc-dev/neofs-node/pkg/core/netmap"
"github.com/nspcc-dev/neofs-node/pkg/services/object/acl/eacl"
)
type netValueReader func(interface{}) (interface{}, error)
type valueWithTime struct {
v interface{}
t time.Time
}
// entity that provides TTL cache interface.
type ttlNetCache struct {
mtx sync.Mutex
ttl time.Duration
sz int
cache *lru.Cache
netRdr netValueReader
}
// complicates netValueReader with TTL caching mechanism.
func newNetworkTTLCache(sz int, ttl time.Duration, netRdr netValueReader) *ttlNetCache {
cache, err := lru.New(sz)
fatalOnErr(err)
return &ttlNetCache{
ttl: ttl,
sz: sz,
cache: cache,
netRdr: netRdr,
}
}
// reads value by the key.
//
// updates the value from the network on cache miss or by TTL.
//
// returned value should not be modified.
func (c *ttlNetCache) get(key interface{}) (interface{}, error) {
c.mtx.Lock()
defer c.mtx.Unlock()
val, ok := c.cache.Peek(key)
if ok {
valWithTime := val.(*valueWithTime)
if time.Since(valWithTime.t) < c.ttl {
return valWithTime.v, nil
}
c.cache.Remove(key)
}
val, err := c.netRdr(key)
if err != nil {
return nil, err
}
c.cache.Add(key, &valueWithTime{
v: val,
t: time.Now(),
})
return val, nil
}
// entity that provides LRU cache interface.
type lruNetCache struct {
mtx sync.Mutex
cache *lru.Cache
netRdr netValueReader
}
// complicates netValueReader with LRU caching mechanism.
func newNetworkLRUCache(sz int, netRdr netValueReader) *lruNetCache {
cache, err := lru.New(sz)
fatalOnErr(err)
return &lruNetCache{
cache: cache,
netRdr: netRdr,
}
}
// reads value by the key.
//
// updates the value from the network on cache miss.
//
// returned value should not be modified.
func (c *lruNetCache) get(key interface{}) (interface{}, error) {
c.mtx.Lock()
defer c.mtx.Unlock()
val, ok := c.cache.Get(key)
if ok {
return val, nil
}
val, err := c.netRdr(key)
if err != nil {
return nil, err
}
c.cache.Add(key, val)
return val, nil
}
// wrapper over TTL cache of values read from the network
// that implements container storage.
type ttlContainerStorage ttlNetCache
func newCachedContainerStorage(v container.Source) container.Source {
const (
containerCacheSize = 100
containerCacheTTL = 30 * time.Second
)
lruCnrCache := newNetworkTTLCache(containerCacheSize, containerCacheTTL, func(key interface{}) (interface{}, error) {
cid := containerSDK.NewID()
err := cid.Parse(key.(string))
if err != nil {
return nil, err
}
return v.Get(cid)
})
return (*ttlContainerStorage)(lruCnrCache)
}
func (s *ttlContainerStorage) Get(cid *containerSDK.ID) (*containerSDK.Container, error) {
val, err := (*ttlNetCache)(s).get(cid.String())
if err != nil {
return nil, err
}
return val.(*containerSDK.Container), nil
}
type ttlEACLStorage ttlNetCache
func newCachedEACLStorage(v eacl.Storage) eacl.Storage {
const (
eaclCacheSize = 100
eaclCacheTTL = 30 * time.Second
)
lruCnrCache := newNetworkTTLCache(eaclCacheSize, eaclCacheTTL, func(key interface{}) (interface{}, error) {
cid := containerSDK.NewID()
err := cid.Parse(key.(string))
if err != nil {
return nil, err
}
return v.GetEACL(cid)
})
return (*ttlEACLStorage)(lruCnrCache)
}
func (s *ttlEACLStorage) GetEACL(cid *containerSDK.ID) (*eaclSDK.Table, error) {
val, err := (*ttlNetCache)(s).get(cid.String())
if err != nil {
return nil, err
}
return val.(*eaclSDK.Table), nil
}
type lruNetmapSource struct {
netState netmap.State
cache *lruNetCache
}
func newCachedNetmapStorage(s netmap.State, v netmap.Source) netmap.Source {
const netmapCacheSize = 10
lruNetmapCache := newNetworkLRUCache(netmapCacheSize, func(key interface{}) (interface{}, error) {
return v.GetNetMapByEpoch(key.(uint64))
})
return &lruNetmapSource{
netState: s,
cache: lruNetmapCache,
}
}
func (s *lruNetmapSource) GetNetMap(diff uint64) (*netmapSDK.Netmap, error) {
return s.getNetMapByEpoch(s.netState.CurrentEpoch() - diff)
}
func (s *lruNetmapSource) GetNetMapByEpoch(epoch uint64) (*netmapSDK.Netmap, error) {
return s.getNetMapByEpoch(epoch)
}
func (s *lruNetmapSource) getNetMapByEpoch(epoch uint64) (*netmapSDK.Netmap, error) {
val, err := s.cache.get(epoch)
if err != nil {
return nil, err
}
return val.(*netmapSDK.Netmap), nil
}
func (s *lruNetmapSource) Epoch() (uint64, error) {
return s.netState.CurrentEpoch(), nil
}