Dear julian, Am 14.10.2016 um 14:26 schrieb Julian Taylor: > On 10/14/2016 08:28 AM, Stefan Priebe - Profihost AG wrote: >> Hello list, >> >> while running the same workload on two machines (single xeon and a dual >> xeon) both with 64GB RAM. >> >> I need to run echo 3 >/proc/sys/vm/drop_caches every 15-30 minutes to >> keep the speed as good as on the non numa system. I'm not sure whether >> this is related to numa. >> >> Is there any sysctl parameter to tune? >> >> Tested with vanilla v4.8.1 >> >> Greets, >> Stefan > > hi, > why do you think this is related to btrfs?
was just an idea as i couldn't find any other difference between those systems. > This is easy to diagnose but recording some kernel stacks during the > problem with perf. you just mean perf top? Does it also show locking problems? As i see not much CPU usage in that case. > The only known issue that has this type of workaround that I know of are > transparent huge pages. I already disabled thp by: echo never > /sys/kernel/mm/transparent_hugepage/enabled cat /proc/meminfo says: HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Greets, Stefan > > cheers, > Julian -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
