On Wed, Mar 4, 2020 at 5:48 AM Jeff Layton <jlayton@xxxxxxxxxx> wrote: > > On Wed, 2020-03-04 at 00:23 +0800, Yan, Zheng wrote: > > On 3/3/20 3:53 AM, Jeff Layton wrote: > > > On Fri, 2020-02-28 at 19:55 +0800, Yan, Zheng wrote: > > > > This series make cephfs client not request caps for open files that > > > > idle for a long time. For the case that one active client and multiple > > > > standby clients open the same file, this increase the possibility that > > > > mds issues exclusive caps to the active client. > > > > > > > > Yan, Zheng (4): > > > > ceph: always renew caps if mds_wanted is insufficient > > > > ceph: consider inode's last read/write when calculating wanted caps > > > > ceph: simplify calling of ceph_get_fmode() > > > > ceph: remove delay check logic from ceph_check_caps() > > > > > > > > fs/ceph/caps.c | 324 +++++++++++++++-------------------- > > > > fs/ceph/file.c | 39 ++--- > > > > fs/ceph/inode.c | 19 +- > > > > fs/ceph/ioctl.c | 2 + > > > > fs/ceph/mds_client.c | 5 - > > > > fs/ceph/super.h | 35 ++-- > > > > include/linux/ceph/ceph_fs.h | 1 + > > > > 7 files changed, 188 insertions(+), 237 deletions(-) > > > > > > > > changes since v2 > > > > - make __ceph_caps_file_wanted more readable > > > > - add patch 5 and 6, which fix hung write during testing patch 1~4 > > > > > > > > > > This patch series causes some serious slowdown in the async dirops > > > patches that I've not yet fully tracked down, and I suspect that they > > > may also be the culprit in these bugs: > > > > > > > slow down which tests? > > > > Most of the simple tests I was doing to sanity check async dirops. > Basically, this script was not seeing speed gain with async dirops > enabled: > > -----------------8<------------------- > #!/bin/sh > > MOUNTPOINT=/mnt/cephfs > TESTDIR=$MOUNTPOINT/test-dirops.$$ > > mkdir $TESTDIR > stat $TESTDIR > echo "Creating files in $TESTDIR" > time for i in `seq 1 10000`; do > echo "foobarbaz" > $TESTDIR/$i > done > echo; echo "sync" > time sync > echo "Starting rm" > time rm -f $TESTDIR/* > echo; echo "rmdir" > time rmdir $TESTDIR > echo; echo "sync" > time sync > -----------------8<------------------- > > It mostly seemed like it was just not getting caps in some cases. > Cranking up dynamic_debug seemed to make the problem go away, which led > me to believe there was probably a race condition in there. > should be fixed by patch "mds: update dentry lease for async create". I saw dput() from ceph_mdsc_release_request() pruned dentry and cleared dir's complete flags. The issue happens if client gets safe replies quickly. I also found that mds revoke Fsx when fragmenting dirfrags. Fixed by following PR https://github.com/ceph/ceph/pull/33719 > At this point, I've gone ahead and merged the async dirops patches into > testing, so if you could rebase this on top of the current testing > branch and repost, I'll test them out again. > > > > https://tracker.ceph.com/issues/44381 > > > > this is because I forgot to check if inode is snap when queue delayed > > check. But it can't explain slow down. > > > > Ok, good to know. > > > > https://tracker.ceph.com/issues/44382 > > > > > > I'm going to drop this series from the testing branch for now, until we > > > can track down the issue. > > > > > > > > Thanks, > -- > Jeff Layton <jlayton@xxxxxxxxxx> >
