Hello, Nirbheek Chauhan <nirbheek <at> gentoo.org> writes: > However, recently, perhaps with 2.6.39, or after I quickly started > filling up my disk again, it has become impossible for me to work for > long periods on my machine. > > Every few minutes, (I guess) when applications do fsync (firefox, > xchat, vim, etc), all applications that use fsync() hang for several > seconds, and applications that use general IO suffer extreme > slowdowns. iotop shows various combinations of the processes listed > below doing writes, and the total write as 2-3MB/s. > > [btrfs-dealloc-] > [btrfs-submit-0] > [btrfs-transacti] > [btrfs-endio-wri] > [flush-btrfs-1] I'm using btrfs under a 2.6.39-ARCH kernel and run into the same issue. In my case the [btrfs-submit-0] and [btrfs-transacti] shows up in iotop and produce 99% of IO at the time a application is frozen. For something like 10 to 30 seconds. After a fresh boot everything runs quiet acceptable and goes worse over the day. If I reboot the unmount process takes a lot of time something up to 8 minutes. After the reboot everything is back to normal. At least for a while. I use snapshots on a daily base and have 20 active snapshots all the time. Maybe this is the reason for the performance impact? > What can I do to debug this issue? What other information should I > supply? Could someone guide me on how to figure out why my machine is > unusable now? I have no solution for this problem. In fact a reboot helps me even if only temporary. I also changed the IO scheduler, switched to laptop mode and remounted the device. Neither of these helped. Maybe someone else has any suggestion? Thanks. Jan Stilow -- 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
