On 2019/1/16 上午8:31, Qu Wenruo wrote: > > > On 2019/1/16 上午1:26, Josef Bacik wrote: >> On Tue, Jan 15, 2019 at 04:15:57PM +0800, Qu Wenruo wrote: >>> This patchset can be fetched from github: >>> https://github.com/adam900710/linux/tree/qgroup_delayed_subtree >>> >>> Which is based on v5.0-rc1. >>> >> >> I've been testing these patches hoping to get rid of the qgroup deadlock that >> these patches are supposed to fix, but instead they make the box completely >> unusable with 100% cpu usage for minutes at a time at every transaction >> commit. > > I'm afraid it's related to the v5.0-rc1 base, not the patchset itself. > > Just try to balance metadata with 16 snapshots, you'll see btrfs bumping > its generation like crazy, no matter if quota is enabled or not. > > And since btrfs is committing transaction like crazy, no wonder it will > do tons of qgroup accounting. > > My bisect leads to commit 64403612b73a94bc7b02cf8ca126e3b8ced6e921 > btrfs: rework btrfs_check_space_for_delayed_refs.
Furthermore, you could try this RFC test case to see the problem. https://patchwork.kernel.org/patch/10761715/ It would only take around 100s for v4.20 but over 500 for v5.0-rc1 with tons of unnecessary transaction committed for nothing, no quota enabled. So I'm afraid that commit is blocking my qgroup patchset. Thanks, Qu > > Thanks, > Qu > >> Thanks, >> >> Josef >> >
signature.asc
Description: OpenPGP digital signature
