Bug 46074

Bug: 46074

Impact:

Product:

GemStone/S 64 Bit

Versions:

3.2.12, 3.2.11, 3.2.10, 3.2.9, 3.2.8, 3.2.7, 3.2.6, 3.2.5, 3.2.4, 3.2.3, 3.2.2, 3.2.1, 3.2

Platform:

All Platforms

Fixed In:

3.2.13

Page Cache Faults during backup

Due to a logic error in the backup process, if the Reclaim GcGem is actively reclaiming pages while the backup is running, the backup can fail with a page cache fault.  The error will include a message similar to:

Page header fault, expected page XXXXXXX frame page XXXXXXX , expected kind 4, found kind X

The error is caused when the Reclaim GcGem inadvertently reclaims a page that the backup still needs to record.

Workaround

Stop the Reclaim GcGem before the backup starts, and restart it when the backup finishes.  You can use these methods to do this:

   System  stopReclaimGem
   System startReclaimGem

Note that while the Reclaim GcGem is shutdown, the stone will build up a backlog of shadowed pages needing to be reclaimed.  The amount can be tracked with the statmonitor stone statistic PagesNeedReclaimSize.  Some additional repository space may be necessary to accommodate this growth.