> There have been numerous reports of stalls that pointed at the problem being > somewhere in the VM. There are multiple roots to the problems which means > dealing with any of the root problems in isolation is tricky to justify on > their own and they would still need integration testing. This patch series > gathers together three different patch sets which in combination should > tackle some of the root causes of latency problems being reported. > > The first patch improves vmscan latency by tracking when pages get reclaimed > by shrink_inactive_list. For this series, the most important results is > being able to calculate the scanning/reclaim ratio as a measure of the > amount of work being done by page reclaim. > > Patches 2 and 3 account for the time spent in congestion_wait() and avoids > calling going to sleep on congestion when it is unnecessary. This is expected > to reduce stalls in situations where the system is under memory pressure > but not due to congestion. > > Patches 4-8 were originally developed by Kosaki Motohiro but reworked for > this series. It has been noted that lumpy reclaim is far too aggressive and > trashes the system somewhat. As SLUB uses high-order allocations, a large > cost incurred by lumpy reclaim will be noticeable. It was also reported > during transparent hugepage support testing that lumpy reclaim was trashing > the system and these patches should mitigate that problem without disabling > lumpy reclaim. Wow, I'm sorry my lazyness bother you. I'll join to test this patch series ASAP and take a feedback soon. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html