README
¶
PACKAGE DOCUMENTATION
package objcache
import "github.com/minio/minio/pkg/objcache"
Package objcache implements in memory caching methods.
VARIABLES
var DefaultExpiry = time.Duration(72 * time.Hour) // 72hrs.
DefaultExpiry represents default time duration value when individual
entries will be expired.
var ErrCacheFull = errors.New("Not enough space in cache")
ErrCacheFull - cache is full.
var ErrKeyNotFoundInCache = errors.New("Key not found in cache")
ErrKeyNotFoundInCache - key not found in cache.
var NoExpiry = time.Duration(0)
NoExpiry represents caches to be permanent and can only be deleted.
TYPES
type Cache struct {
// OnEviction - callback function for eviction
OnEviction func(key string)
// contains filtered or unexported fields
}
Cache holds the required variables to compose an in memory cache system
which also provides expiring key mechanism and also maxSize.
func New(maxSize uint64, expiry time.Duration) *Cache
New - Return a new cache with a given default expiry duration. If the
expiry duration is less than one (or NoExpiry), the items in the cache
never expire (by default), and must be deleted manually.
func (c *Cache) Create(key string, size int64) (w io.WriteCloser, err error)
Create - validates if object size fits with in cache size limit and
returns a io.WriteCloser to which object contents can be written and
finally Close()'d. During Close() we checks if the amount of data
written is equal to the size of the object, in which case it saves the
contents to object cache.
func (c *Cache) Delete(key string)
Delete - delete deletes an entry from the cache.
func (c *Cache) DeleteExpired()
DeleteExpired - deletes all the expired entries from the cache.
func (c *Cache) Open(key string) (io.ReadSeeker, error)
Open - open the in-memory file, returns an in memory read seeker.
returns an error ErrNotFoundInCache, if the key does not exist.
func (c *Cache) StopExpiry()
StopExpiry sends a message to the expiry routine to stop expiring cached
entries. NOTE: once this is called, cached entries will not be expired
if the consume has called this.
Documentation
¶
Overview ¶
Package objcache implements in memory caching methods.
Package objcache implements in memory caching methods.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var DefaultBufferRatio = uint64(10)
DefaultBufferRatio represents default ratio used to calculate the individual cache entry buffer size.
var DefaultExpiry = time.Duration(72 * time.Hour) // 72hrs.
DefaultExpiry represents default time duration value when individual entries will be expired.
var DefaultGCPercent = 20
DefaultGCPercent represents default garbage collection target percentage.
var ErrCacheFull = errors.New("Not enough space in cache")
ErrCacheFull - cache is full.
var ErrExcessData = errors.New("Attempted excess write on cache")
ErrExcessData - excess data was attempted to be written on cache.
var ErrKeyNotFoundInCache = errors.New("Key not found in cache")
ErrKeyNotFoundInCache - key not found in cache.
var NoExpiry = time.Duration(0)
NoExpiry represents caches to be permanent and can only be deleted.
Functions ¶
This section is empty.
Types ¶
type Cache ¶
type Cache struct {
// OnEviction - callback function for eviction
OnEviction func(key string)
// contains filtered or unexported fields
}
Cache holds the required variables to compose an in memory cache system which also provides expiring key mechanism and also maxSize.
func New ¶
New - Return a new cache with a given default expiry duration. If the expiry duration is less than one (or NoExpiry), the items in the cache never expire (by default), and must be deleted manually.
func (*Cache) Create ¶
Create - validates if object size fits with in cache size limit and returns a io.WriteCloser to which object contents can be written and finally Close()'d. During Close() we checks if the amount of data written is equal to the size of the object, in which case it saves the contents to object cache.
func (*Cache) Open ¶
Open - open the in-memory file, returns an in memory read seeker. returns an error ErrNotFoundInCache, if the key does not exist. Returns ErrKeyNotFoundInCache if entry's lastAccessedTime is older than objModTime.
Source Files