From: Vineet Gupta <[email protected]> Date: Wed, 4 Sep 2013 17:17:15 +0530
> copying large files to a NFS mounted host was taking absurdly large > time. > > Turns out that TX BD reclaim had a sublte bug. > > Loop starts off from @txbd_dirty cursor and stops when it hits a BD > still in use by controller. However when it stops it needs to keep the > cursor at that very BD to resume scanning in next iteration. However it > was erroneously incrementing the cursor, causing the next scan(s) to > fail too, unless the BD chain was completely drained out. > > [ARCLinux]$ ls -l -sh /disk/log.txt > 17976 -rw-r--r-- 1 root root 17.5M Sep /disk/log.txt > > ========== Before ===================== > [ARCLinux]$ time cp /disk/log.txt /mnt/. > real 31m 7.95s > user 0m 0.00s > sys 0m 0.10s > > ========== After ===================== > [ARCLinux]$ time cp /disk/log.txt /mnt/. > real 0m 24.33s > user 0m 0.00s > sys 0m 0.19s > > Signed-off-by: Vineet Gupta <[email protected]> Applied. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
