diff --git a/weed/filer/reader_pattern.go b/weed/filer/reader_pattern.go index 38a51d788..e32f7fc2d 100644 --- a/weed/filer/reader_pattern.go +++ b/weed/filer/reader_pattern.go @@ -5,6 +5,8 @@ type ReaderPattern struct { lastReadStopOffset int64 } +const ModeChangeLimit = 3 + // For streaming read: only cache the first chunk // For random read: only fetch the requested range, instead of the whole chunk @@ -17,9 +19,13 @@ func NewReaderPattern() *ReaderPattern { func (rp *ReaderPattern) MonitorReadAt(offset int64, size int) { if rp.lastReadStopOffset == offset { - rp.isSequentialCounter++ + if rp.isSequentialCounter < ModeChangeLimit { + rp.isSequentialCounter++ + } } else { - rp.isSequentialCounter-- + if rp.isSequentialCounter > -ModeChangeLimit { + rp.isSequentialCounter-- + } } rp.lastReadStopOffset = offset + int64(size) } diff --git a/weed/mount/page_writer_pattern.go b/weed/mount/page_writer_pattern.go index 1ec9c9d4c..1ebcc19eb 100644 --- a/weed/mount/page_writer_pattern.go +++ b/weed/mount/page_writer_pattern.go @@ -6,6 +6,8 @@ type WriterPattern struct { chunkSize int64 } +const ModeChangeLimit = 3 + // For streaming write: only cache the first chunk // For random write: fall back to temp file approach // writes can only change from streaming mode to non-streaming mode @@ -20,9 +22,13 @@ func NewWriterPattern(chunkSize int64) *WriterPattern { func (rp *WriterPattern) MonitorWriteAt(offset int64, size int) { if rp.lastWriteStopOffset == offset { - rp.isSequentialCounter++ + if rp.isSequentialCounter < ModeChangeLimit { + rp.isSequentialCounter++ + } } else { - rp.isSequentialCounter-- + if rp.isSequentialCounter > -ModeChangeLimit { + rp.isSequentialCounter-- + } } rp.lastWriteStopOffset = offset + int64(size) }