Download/kernel/rhel6/042stab068.8/changes

Changes

Since 042stab065.3:

• [mm] possible memory corruption has been fixed by preventing reclaiming of pages in the writeback (PSBM-16442)
• [ploop] possible deadlock on destroying map has been fixed (PSBM-16627)
• [ubc/mm] A new strict page cache isolation feature (PSBM-16955)
  • This feature disables bouncing pagecache pages between host and containers on physpages shortage in container. Internal reclaimer will drop cached data if container exceeded its physpages limit and pagecache isolation turned on.
  • Current state: /proc/bc/<id>/debug:pagecache_isolation (disabled by default)
  • sysctls:
    • ubc.pagecache_isolation = 0|1 turn off|on isolation for all containers
    • ubc.pagecache_isolation_on = <id> turn on for container <id> (write only)
    • ubc.pagecache_isolation_off = <id> turn off for container <id> (write only)
• [mm] per-bc pagecache should be shrinked proportionally now (PSBM-15799)
• [mm] debug trace events has been added into shrink_zone and shrink_gang
• [dcache] introduce per-bc dcache lru lists with real time shrink. Underlying dcache can be immediately shrunk if sysctl "ubc.dcache_no_vzfs_cache" is set (PSBM-16072)
• [vSwap] virtual vSwap feature has been introduced => now vSwap does not require free physical swap on the HN (PSBM-16764)
• [pagecache] enchanted version of memory scheduler: shadow gangs, reclaimer takes timestamps into the consideration, etc. (PSBM-15796)
  • vmscan priority is calculated for all LRU vectors according to its memory usage/limit and age of LRU lists.
  • sysctls:
    • vm.usage_factor (default 2)
    • vm.shadow_factor (default 8)
    • vm.age_factor (default 8)
    • priority = 12 + usage * usage_factor / limit + shadow * shadow_factor / limit (for shadow part only) + age * age_factor / max_age
• [ubc/dcache] fix endless oom postponing in dcache reclaimer (PSBM-17067, PSBM-17069)
• [mm] the number of vmscan prios has been increased from 25 to 42. vmscan iterator has been fixed. (PSBM-15799)
• [cpt] kernel panic has been fixed due to DEAD task restoration attempt (PCLIN-30483, PSBM-17107)
• [mm] deadlock in kswapd near oom condition has been fixed (PSBM-17100)
• [mm] a new formula has been implemented for pagecache reclaimer, the reclaimer should become more indulgent for small Containers with old pages
  • + some stats is visible now in /proc/meminfo and /proc/bc/*/meminfo in case ve.meminfo==2 (PSBM-15799)
• [devpts] handle dentry allocation failure properly in devpts_pty_new() (#1758)