[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: ext4 and extremely slow filesystem traversal



On 13/03/2013 03:52, Theodore Ts'o wrote:
>
> Did you sort results from readdir() by inode number?  i.e., such as
> what the following LD_PRELOAD hack does?
> 
> https://git.kernel.org/cgit/fs/ext2/e2fsprogs.git/tree/contrib/spd_readdir.c?h=maint

  I don't think I tried this specific hack, I'm having a go right now.
Is is still useful if each directory only holds a few inodes ?


>>   Right now I don't even know how to analyze my filesystem further.
>> Sorry for not being able to describe it more accurately. I'm in search
>> for any advice or direction to improve this situation. While keeping
>> using ext4 of course :).
> 
> Try running "e2fsck -fv /dev/XXX" and send me the output.
> 
> Also useful would be the output of "e2freefrag /dev/XXX" and "dumpe2fs -h"

  Information attached. Dumpfs said: dumpe2fs 1.42.5 (29-Jul-2012).

  Thanks for your help !
Device: /dev/vg-raid3/xyz
Blocksize: 4096 bytes
Total blocks: 78643200
Free blocks: 26099944 (33.2%)

Min. free extent: 4 KB 
Max. free extent: 557632 KB
Avg. free extent: 468 KB

HISTOGRAM OF FREE EXTENT SIZES:
Extent Size Range :  Free extents   Free Blocks  Percent
    4K...    8K-  :         52301         52301    0.20%
    8K...   16K-  :         36907         87967    0.34%
   16K...   32K-  :         36063        187694    0.72%
   32K...   64K-  :         41123        433236    1.66%
   64K...  128K-  :         26411        579943    2.22%
  128K...  256K-  :         16236        745344    2.86%
  256K...  512K-  :          6073        513906    1.97%
  512K... 1024K-  :          4378        774518    2.97%
    1M...    2M-  :           699        244092    0.94%
    2M...    4M-  :           392        280118    1.07%
    4M...    8M-  :           289        420979    1.61%
    8M...   16M-  :           308        906478    3.47%
   16M...   32M-  :           289       1520835    5.83%
   32M...   64M-  :            67        668899    2.56%
   64M...  128M-  :           479      13748140   52.67%
  128M...  256M-  :            16        875692    3.36%
  256M...  512M-  :            39       3920394   15.02%
  512M... 1024M-  :             1        139408    0.53%
e2fsck 1.41.12 (17-May-2010)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information

 9345910 inodes used (47.54%)
   12447 non-contiguous files (0.1%)
      34 non-contiguous directories (0.0%)
         # of inodes with ind/dind/tind blocks: 0/0/0
         Extent depth histogram: 9345889/11
52543256 blocks used (66.81%)
       0 bad blocks
       1 large file

 3633315 regular files
 5712586 directories
       0 character device files
       0 block device files
       0 fifos
       0 links
       0 symbolic links (0 fast symbolic links)
       0 sockets
--------
 9345901 files

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]