package chunk_cache import ( "fmt" "path" "sort" "github.com/chrislusf/seaweedfs/weed/glog" "github.com/chrislusf/seaweedfs/weed/storage" "github.com/chrislusf/seaweedfs/weed/storage/types" ) type OnDiskCacheLayer struct { diskCaches []*ChunkCacheVolume } func NewOnDiskCacheLayer(dir, namePrefix string, diskSizeMB int64, segmentCount int) *OnDiskCacheLayer { volumeCount, volumeSize := int(diskSizeMB/30000), int64(30000) if volumeCount < segmentCount { volumeCount, volumeSize = segmentCount, diskSizeMB/int64(segmentCount) } c := &OnDiskCacheLayer{} for i := 0; i < volumeCount; i++ { fileName := path.Join(dir, fmt.Sprintf("%s_%d", namePrefix, i)) diskCache, err := LoadOrCreateChunkCacheVolume(fileName, volumeSize*1024*1024) if err != nil { glog.Errorf("failed to add cache %s : %v", fileName, err) } else { c.diskCaches = append(c.diskCaches, diskCache) } } // keep newest cache to the front sort.Slice(c.diskCaches, func(i, j int) bool { return c.diskCaches[i].lastModTime.After(c.diskCaches[j].lastModTime) }) return c } func (c *OnDiskCacheLayer) setChunk(needleId types.NeedleId, data []byte) { if c.diskCaches[0].fileSize+int64(len(data)) > c.diskCaches[0].sizeLimit { t, resetErr := c.diskCaches[len(c.diskCaches)-1].Reset() if resetErr != nil { glog.Errorf("failed to reset cache file %s", c.diskCaches[len(c.diskCaches)-1].fileName) return } for i := len(c.diskCaches) - 1; i > 0; i-- { c.diskCaches[i] = c.diskCaches[i-1] } c.diskCaches[0] = t } c.diskCaches[0].WriteNeedle(needleId, data) } func (c *OnDiskCacheLayer) getChunk(needleId types.NeedleId) (data []byte) { var err error for _, diskCache := range c.diskCaches { data, err = diskCache.GetNeedle(needleId) if err == storage.ErrorNotFound { continue } if err != nil { glog.Errorf("failed to read cache file %s id %d", diskCache.fileName, needleId) continue } if len(data) != 0 { return } } return nil } func (c *OnDiskCacheLayer) shutdown() { for _, diskCache := range c.diskCaches { diskCache.Shutdown() } }