Cassandra
  1. Cassandra
  2. CASSANDRA-3623

use MMapedBuffer in CompressedSegmentedFile.getSegment

    Details

    • Type: Improvement Improvement
    • Status: Resolved
    • Priority: Major Major
    • Resolution: Won't Fix
    • Fix Version/s: 1.1.0
    • Component/s: Core
    • Labels:

      Description

      CompressedSegmentedFile.getSegment seem to open a new file and doesnt seem to use the MMap and hence a higher CPU on the nodes and higher latencies on reads.

      This ticket is to implement the TODO mentioned in CompressedRandomAccessReader

      // TODO refactor this to separate concept of "buffer to avoid lots of read() syscalls" and "compression buffer"
      but i think a separate class for the Buffer will be better.

        Activity

        Vijay created issue -
        Vijay made changes -
        Field Original Value New Value
        Attachment 0001-MMaped-Compression-segmented-file.patch [ 12508352 ]
        Vijay made changes -
        Status Open [ 1 ] Patch Available [ 10002 ]
        Jonathan Ellis made changes -
        Labels compression
        Reviewer xedin
        Vijay made changes -
        Vijay made changes -
        Attachment 0001-MMaped-Compression-segmented-file-v3.patch [ 12508655 ]
        Attachment 0002-tests-for-MMaped-Compression-segmented-file-v3.patch [ 12508656 ]
        Attachment MMappedIO-Performance.docx [ 12508657 ]
        Attachment CRC+MMapIO.xlsx [ 12508658 ]
        Vijay made changes -
        Attachment CRC+MMapIO.xlsx [ 12508658 ]
        Vijay made changes -
        Attachment MMappedIO-Performance.docx [ 12508657 ]
        Vijay made changes -
        Attachment MMappedIO-Performance.docx [ 12508701 ]
        Attachment CRC+MMapIO.xlsx [ 12508702 ]
        Jonathan Ellis made changes -
        Reviewer xedin yukim
        Vijay made changes -
        Status Patch Available [ 10002 ] Resolved [ 5 ]
        Resolution Won't Fix [ 2 ]
        Gavin made changes -
        Workflow no-reopen-closed, patch-avail [ 12645702 ] patch-available, re-open possible [ 12749347 ]
        Gavin made changes -
        Workflow patch-available, re-open possible [ 12749347 ] reopen-resolved, no closed status, patch-avail, testing [ 12754197 ]

          People

          • Assignee:
            Vijay
            Reporter:
            Vijay
            Reviewer:
            Yuki Morishita
          • Votes:
            0 Vote for this issue
            Watchers:
            1 Start watching this issue

            Dates

            • Created:
              Updated:
              Resolved:

              Development