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Enabling lazy counters damages filesystem

To: xfs@xxxxxxxxxxx
Subject: Enabling lazy counters damages filesystem
From: Marcin Mirosław <marcin@xxxxxxxx>
Date: Wed, 28 Apr 2010 16:34:25 +0200
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Hello,
Please look at this:
# mkfs.xfs -f /dev/malowazne/test
meta-data=/dev/malowazne/test    isize=256    agcount=4, agsize=524288 blks
         =                       sectsz=512   attr=2
data     =                       bsize=4096   blocks=2097152, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal log           bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=0
realtime =none                   extsz=4096   blocks=0, rtextents=0

# xfs_check /dev/malowazne/test
# xfs_check /dev/malowazne/test

It's still clean.

# xfs_admin -c 1 /dev/malowazne/test
Enabling lazy-counters
# xfs_check /dev/malowazne/test
sb_features2 (0xa) not same as sb_bad_features2 (0x8)

Not good, let's repair fs:

# xfs_repair /dev/malowazne/test
Phase 1 - find and verify superblock...
superblock has a features2 mismatch, correcting
writing modified primary superblock
Phase 2 - using internal log
        - zero log...
        - scan filesystem freespace and inode maps...
        - found root inode chunk
Phase 3 - for each AG...
        - scan and clear agi unlinked lists...
        - process known inodes and perform inode discovery...
        - agno = 0
        - agno = 1
        - agno = 2
        - agno = 3
        - process newly discovered inodes...
Phase 4 - check for duplicate blocks...
        - setting up duplicate extent list...
        - check for inodes claiming duplicate blocks...
        - agno = 0
        - agno = 1
        - agno = 2
        - agno = 3
Phase 5 - rebuild AG headers and trees...
        - reset superblock...
Phase 6 - check inode connectivity...
        - resetting contents of realtime bitmap and summary inodes
        - traversing filesystem ...
        - traversal finished ...
        - moving disconnected inodes to lost+found ...
Phase 7 - verify and correct link counts...
done

Now i'm trying to turn off lazy counters:

# xfs_admin -c 0 /dev/malowazne/test
Disabling lazy-counters
# xfs_check /dev/malowazne/test
sb_features2 (0x8) not same as sb_bad_features2 (0xa)
# xfs_repair /dev/malowazne/test
Phase 1 - find and verify superblock...
superblock has a features2 mismatch, correcting
writing modified primary superblock
Phase 2 - using internal log
        - zero log...
        - scan filesystem freespace and inode maps...
        - found root inode chunk
Phase 3 - for each AG...
        - scan and clear agi unlinked lists...
        - process known inodes and perform inode discovery...
        - agno = 0
        - agno = 1
        - agno = 2
        - agno = 3
        - process newly discovered inodes...
Phase 4 - check for duplicate blocks...
        - setting up duplicate extent list...
        - check for inodes claiming duplicate blocks...
        - agno = 0
        - agno = 1
        - agno = 2
        - agno = 3
Phase 5 - rebuild AG headers and trees...
        - reset superblock...
Phase 6 - check inode connectivity...
        - resetting contents of realtime bitmap and summary inodes
        - traversing filesystem ...
        - traversal finished ...
        - moving disconnected inodes to lost+found ...
Phase 7 - verify and correct link counts...
done

# mount /dev/malowazne/test /mnt/test
# xfs_info /dev/malowazne/test
meta-data=/dev/mapper/malowazne-test isize=256    agcount=4,
agsize=524288 blks
         =                       sectsz=512   attr=2
data     =                       bsize=4096   blocks=2097152, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal               bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

So as you can see lazy conters are still turn on.
I'm using:
# mkfs.xfs -V
mkfs.xfs version 3.0.3
# uname -r
2.6.33-zen2

The same problem noticed with kernel-2.6.28-r9 with grsecurity, and with
xfsprogs-3.0.0 .
Is this behaviour bug or i don't know about something that i should?:)

Regards!
Marcin









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