>>>> INFO: task systemd-journal:20876 blocked for more than 120 seconds. >>>> [ 5037.962603] Tainted: G C O 4.14.9-1-ARCH #1 >>>> [ 5037.962609] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables >>>> this message. >>>> [ 5037.962616] systemd-journal D 0 20876 20860 0x00000100 >>>> [ 5037.962622] Call Trace: >>>> [ 5037.962635] ? __schedule+0x290/0x890 >>>> [ 5037.962640] ? __slab_free+0x14e/0x300 >>>> [ 5037.962645] ? _copy_to_iter+0x8f/0x3d0 >>>> [ 5037.962651] schedule+0x2f/0x90 >>>> [ 5037.962704] btrfs_tree_read_lock+0xb6/0x100 [btrfs] >>> >>> Still some tree write is blocking all incoming read. >>> >>> BTW, did your tests include any send and relocation operations? >>> >>> IIRC there is a bug that makes send and relocation (I'm not sure though) >>> will cause similar problem. >> >> No. I’m doing nothing btrfs-specific at all, it’s just whatever >> systemd-nspawn —ephemeral does. > > So, only systemd-nspwan --ephemeral, and nothing else at all? > > Even nothing happened inside the container?
Gotcha. (Sorry for missing that) Inside the container, snapper might be invoked. Here are the snippets: snapper -c root create-config -t ubos-default / snapper setup-quota snapper -c root create --type pre --print-number snapper -c root create --type post --pre-number <n> Here is the snapper config: # Snapper default configuration for UBOS. # # subvolume to snapshot SUBVOLUME="/" # filesystem type FSTYPE="btrfs" # btrfs qgroup for space aware cleanup algorithms QGROUP="" # fraction of the filesystems space the snapshots may use SPACE_LIMIT="0.2" # users and groups allowed to work with config ALLOW_USERS="" ALLOW_GROUPS="" # sync users and groups from ALLOW_USERS and ALLOW_GROUPS to .snapshots # directory SYNC_ACL="no" # start comparing pre- and post-snapshot in background after creating # post-snapshot BACKGROUND_COMPARISON="no" # run daily number cleanup NUMBER_CLEANUP="yes" # limit for number cleanup; unit is seconds NUMBER_MIN_AGE="1800" NUMBER_LIMIT="50" NUMBER_LIMIT_IMPORTANT="10" # create hourly snapshots TIMELINE_CREATE="no" # cleanup hourly snapshots after some time TIMELINE_CLEANUP="yes" # limits for timeline cleanup; unit is seconds TIMELINE_MIN_AGE="1800" TIMELINE_LIMIT_HOURLY="12" TIMELINE_LIMIT_DAILY="7" TIMELINE_LIMIT_WEEKLY="0" TIMELINE_LIMIT_MONTHLY="6" TIMELINE_LIMIT_YEARLY="0" # cleanup empty pre-post-pairs EMPTY_PRE_POST_CLEANUP="yes" # limits for empty pre-post-pair cleanup EMPTY_PRE_POST_MIN_AGE="1800" -- 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
