Hello Arne, However, I remember that i have hit this panic in several kernel version. And i will double check it tomorrow when i am in the work.. If possible, i will send you the message from dmesg. Thanks, Wang > Hello Wang, > > On 03/31/13 03:44, Wang Shilong wrote: >> Hello Arne, Jan, >> >> When i run stresstest with quota enabled, i hit a panic where >> btrfs_find_all_roots() is called. Would you please double check it. >> > > On what kernel version do you hit this (git commit id preferred)? > Can you send us the message from dmesg? > > Thanks, > arne > >> stresstest -n 10000 -t 4. >> >> Maybe there is still race condition when walking backref trees, Jan >> would you please check the backref.c .. >> btrfs_find_all_roots() is called in btrfs_qgroup_account_ref () to find >> all roots that reference a extent. I think this is called because >> >> we introduce referenced/exclusive concepts. The point is that i think >> this concept's disadvantages outweigh the advantages: >> <1> >> walking backref tree is really time-consuming. >> <2> referenced/exclusive makes it really complex when snapshot happens. >> <3> quota has a high coupling with other module. >> I'd prefer to just keep referenced value, it is not be elegant, but >> it helps more. >> >> Thanks, >> Wang >> >> >> >> >> > -- 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
