Thanks for the info. I have checked the comment inside the test case, which state that: # And unfortunately, btrfs send is one of these operations, and will cause # softlock or OOM on systems with small memory(<4G). To my experience, this will stuck on a system with 32G memory too. And in the end of the script, it says: # send out the subvolume, and it will either: # 1) OOM since memory is allocated inside a O(n^3) loop # 2) Softlock since time consuming backref walk is called without scheduling. I can see the soft lockup behaviour (I guess this is the second result listed above?) from dmesg as described in https://bugs.launchpad.net/bugs/1718925 So I'm curious that does anyone know how long it might take if this test works? Tried 8 hours as a timeout limit but no luck. Or maybe this test is totally broken? Thanks! On Tue, Oct 17, 2017 at 9:03 PM, Jeff Mahoney <jeffm@xxxxxxxx> wrote: > On 10/17/17 8:46 AM, Qu Wenruo wrote: >> >> >> On 2017年10月17日 19:11, Po-Hsu Lin wrote: >>> Hello Chris, >>> >>> I can reproduce this on my side too, with Ubuntu 16.04 + 4.4.0-97 kernel. >> >> Btrfs/130 is a known bug. >> >> I submitted it to raise the concern about such situation and purposed >> one possible solution (just disable deduped file detection). >> >> But the solution doesn't get accepted. > > It also works very well as a performance test for qgroup runtime > improvements. :) > > -Jeff > >> Thanks, >> Qu >>> >>> PREEMPT config: >>> $ cat config-4.4.0-97-generic | grep PREEMPT >>> CONFIG_PREEMPT_NOTIFIERS=y >>> # CONFIG_PREEMPT_NONE is not set >>> CONFIG_PREEMPT_VOLUNTARY=y >>> # CONFIG_PREEMPT is not set >>> >>> Bug reports on launchpad: >>> https://bugs.launchpad.net/bugs/1718925 >>> https://bugs.launchpad.net/bugs/1717443 >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >> > > > -- > Jeff Mahoney > SUSE Labs > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
