{"action":"created","issue":{"url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3409","labels_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3409/labels{/name}","comments_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3409/comments","events_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3409/events","html_url":"https://github.com/zfsonlinux/zfs/issues/3409","id":75997300,"number":3409,"title":"txg_sync, z_null_iss and txg_quiesce freezes","user":{"login":"hallabro","id":2978237,"avatar_url":"https://avatars.githubusercontent.com/u/2978237?v=3","gravatar_id":"","url":"https://api.github.com/users/hallabro","html_url":"https://github.com/hallabro","followers_url":"https://api.github.com/users/hallabro/followers","following_url":"https://api.github.com/users/hallabro/following{/other_user}","gists_url":"https://api.github.com/users/hallabro/gists{/gist_id}","starred_url":"https://api.github.com/users/hallabro/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/hallabro/subscriptions","organizations_url":"https://api.github.com/users/hallabro/orgs","repos_url":"https://api.github.com/users/hallabro/repos","events_url":"https://api.github.com/users/hallabro/events{/privacy}","received_events_url":"https://api.github.com/users/hallabro/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":18,"created_at":"2015-05-13T14:12:38Z","updated_at":"2015-05-14T22:19:56Z","closed_at":null,"body":"I have an issue very similiar to https://github.com/zfsonlinux/zfs/issues/3235 where txg_sync, z_null_iss/0 and txg_quiesce are stuck and consuming CPU. Any processes trying to access some files inside the filesystem will get stuck as well.\r\n\r\nI cannot restart the system but have to turn the power off.\r\n\r\nSome information and stack traces:\r\n`slabinfo` http://pastebin.com/JLyqJKJA\r\n`kmem/slab` http://pastebin.com/sRY3BWQn\r\n`arcstats` http://pastebin.com/T6tm8702\r\n`meminfo` http://pastebin.com/qDrDipkV\r\n`SysRq-t` http://paste.ubuntu.com/11109410/\r\n`SysRq-w` http://pastebin.com/qn8qqKiB\r\n\r\nWorth mentioning is also that I do use dmcrypt on the block devices, in case it makes any difference.\r\nThe freeze occured shortly after firing up rtorrent to start seeding a torrent.\r\n\r\nI have no problems with \"normal\" IO (moving and opening files), however.\r\n"},"comment":{"url":"https://api.github.com/repos/zfsonlinux/zfs/issues/comments/102186368","html_url":"https://github.com/zfsonlinux/zfs/issues/3409#issuecomment-102186368","issue_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3409","id":102186368,"user":{"login":"behlendorf","id":148917,"avatar_url":"https://avatars.githubusercontent.com/u/148917?v=3","gravatar_id":"","url":"https://api.github.com/users/behlendorf","html_url":"https://github.com/behlendorf","followers_url":"https://api.github.com/users/behlendorf/followers","following_url":"https://api.github.com/users/behlendorf/following{/other_user}","gists_url":"https://api.github.com/users/behlendorf/gists{/gist_id}","starred_url":"https://api.github.com/users/behlendorf/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/behlendorf/subscriptions","organizations_url":"https://api.github.com/users/behlendorf/orgs","repos_url":"https://api.github.com/users/behlendorf/repos","events_url":"https://api.github.com/users/behlendorf/events{/privacy}","received_events_url":"https://api.github.com/users/behlendorf/received_events","type":"User","site_admin":false},"created_at":"2015-05-14T22:19:56Z","updated_at":"2015-05-14T22:19:56Z","body":"@dweeezil other OpenZFS platforms might not be able to trigger this as easily because they never allow `zfs_arc_min` to drop below 1/32 of total memory."}}