7 Replies Latest reply on Jun 19, 2010 10:37 AM by Keyur_makwana

    Problems with Dynamic Remastering (DRM) with on Linux Itanium

      One of my customers is having severe RAC performance issues, which appeared three times so far. Each time, the performance impact lasted around 10 minutes and caused basically a hang of the application. ASH investigation revealed that the time frame of performance issues exactly matches a DRM operation of the biggest segment of the database. During the problematic time period, there are +50 instead of 2-3 active sessions and they are mostly waiting for gc related events: "gc buffer busy","gc cr block busy", "gc cr block 2-way", "gc current block 2-way", "gc current request", "gc current grant busy", etc.

      In addition, there is one single session which has wait event "kjbdrmcvtq lmon drm quiesce: ping completion" (on instance 1) and 1-3 sessions with wait event "gc remaster". (on instance 2)

      Does anybody have any experience with DRM problems with on Linux Itanium?

      I know that it is possible to deactive DRM, but usually it should be beneficial to have it enabled. I could not find any reports of performance impact during DRM operation on metalink. Support is involved but clueless.