[regression] NBS causes sudden loss of performance after surface resizes

So, seems what was happening was one of the three buffers was lingering in the mcl::BufferVault without ever being freed again after a resize occurred. Correcting code to reallocate buffers properly.

Actually, this would be bug 1557442. We just didn't fix it properly last time...

Fix is committed to lp:mir/0.23, although it hasn't been reviewed in any branch yet.

Just queuing up the release. Its not landed to trunk, but it is part of testing and assembling the mir silo. Moving back to in progress.

Status changed to 'Confirmed' because the bug affects multiple users.

I just hit this bug on desktop; resizing flicker to be very large.

This bug was fixed in the package mir - 0.23.0+16.10.20160602.1-0ubuntu1

---------------
mir (0.23.0+16.10.20160602.1-0ubuntu1) yakkety; urgency=medium

  [ Kevin DuBois ]
  * New upstream release 0.23.0 (https://launchpad.net/mir/+milestone/0.23.0)
    - ABI summary:
      . mirclient ABI unchanged at 9
      . mirserver ABI bumped to 40
      . mircommon ABI bumped at 6
      . mirplatform ABI unchanged at 11
      . mirprotobuf ABI unchanged at 3
      . mirplatformgraphics ABI unchanged at 9
      . mirclientplatform ABI unchanged at 5
      . mirinputplatform ABI unchanged at 5
    - Enhancements:
      . Enable internal usage of more flexible graphics buffer submission,
        precursing client API additions.
    - Bug fixes:
      . Potential NBS performance loss after resize (LP: #1579076)
      . Performance loss with NBS and overlays on (LP: #1578159)
      . Mir crashes with useless backtrace when mg::Platform methods throw
        (LP: #1553549)
      . Virtual output is not removed when screencast client disappears
        (LP: #1573572)
      . Can't VT switch from mir_demo_server (any more) (LP: #1576260)
      . mir_demo_server(_minimal): Window movement/resizing stops responding
        when the cursor leaves the surface, and can lead to windows 1px wide
        and unrecoverable. (LP: #1447886)
      . Virtual display output configuration is set to LVDS (LP: #1573782)
      . Mir-on-X11 doesn't pass Alt+primary button drag to Mir (LP: #1575765)
      . Mir-on-X11 breaks mir_proving_server resize logic (LP: #1575192)
      . Resizing can crash mir_demo_server (LP: #1575211)
      . [regression] Cursor stops at phantom edge on M10 and N7 (LP: #1580774)
      . [regression] MIR_CLIENT_PERF_REPORT is showing bogus render times and
        buffer lag (LP: #1581368)
      . Test failures in ClientLogging.reports_performance due to the above
        fix. (LP: #1583970, LP: #1584603, LP: #1584605)
      . Do not throw when creating some objects under HWC 1.5 (LP: #1583086)
      . Correct black frame issue under Xmir (LP: #1584784)

  [ Tarmac, Kevin DuBois <email address hidden>, Daniel van Vugt <email address hidden>, Andreas Pokorny <email address hidden>, Alberto Aguirre ]
  * 0.23.0 Mir release

 -- Kevin DuBois <email address hidden> Thu, 02 Jun 2016 13:18:03 +0000