Uploaded image for project: 'Couchbase Server'
  1. Couchbase Server
  2. MB-62455

[BP 7.2.6] Magma seqIndex wasted space may consume all compression gains

    XMLWordPrintable

Details

    • 0

    Description

      We noticed in CBSE-16847 that the sequence index wasted space was consuming half the total disk usage on a single node, 1TB of 2TB. This was a result of high compression(2X) in this case resulting in wasted space being allowed to grow up to the 50% fragmentation compared to the total data_size thus negating the gains made by compression.

      The fix for this involves scaling WastedSpace usage during compaction trigger computation with compression ratio of L4 ie. logical size vs physical.

      We will also have to add stats to help debugging this scaling if issues arise.

      Attachments

        Issue Links

          is a backport of

          Task - A task that needs to be done. MB-61584 Magma seqIndex wasted space may consume all compression gains

          • Major - Major loss of function.
          • Resolved
          No reviews matched the request. Check your Options in the drop-down menu of this sections header.

          Activity

            People

              vibhav.sp Vibhav S P
              srinath.duvuru Srinath Duvuru
              Votes:
              0 Vote for this issue
              Watchers:
              4 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved:

                Gerrit Reviews

                  There are no open Gerrit changes

                  PagerDuty