[Ocfs2-users] fsck.ocfs2 using huge amount of memory?

[Ulf Zimmermann]

> -----Original Message-----
> From: Joel Becker [mailto:Joel.Becker at oracle.com]
> Sent: Thursday, May 20, 2010 6:31 PM
> To: Ulf Zimmermann
> Cc: ocfs2-users at oss.oracle.com
> Subject: Re: [Ocfs2-users] fsck.ocfs2 using huge amount of memory?
> 
> On Thu, May 20, 2010 at 06:00:19PM -0700, Ulf Zimmermann wrote:
> > We are setting up 2 new EL5 U4 machines to replace our current
> database servers running our demo environment. We use 3Par SANs and
> their snap clone options. The current production system we snap  clone
> from is EL4 U5 with ocfs2 1.2.9, the new servers have ocfs2 1.4.3
> installed. Part of the refresh process is to run fsck.ocfs2 on the
> volume to recover, but right now as I am trying to run it on our 700GB
> volume it shows a virtual memory size of 21.9GB, resident of 10GB and
> it is killing the machine with swapping (24GB physical memory).
> >
> > Can anyone enlighten what is going on?
> 
> 	How big are your filesystems?  Can we get the output of
> debugfs.ocfs2 -R 'stats' /dev/xxx?
> 	Recent fsck.ocfs2 knows how to build its own I/O cache for
> significant speed improvements.  It only tries to get as much cache as
> the filesystem actually needs, and no more than half of system memory.
> That's why I'm asking for your filesystem size - I'm guessing you have
> more than 12GB of used space on the filesystem, so fsck.ocfs2 is trying
> to grab that much cache.

dbdemo01 root /home/atcit # debugfs.ocfs2 -R 'stats' /dev/mapper/u01
        Revision: 0.90
        Mount Count: 0   Max Mount Count: 20
        State: 0   Errors: 0
        Check Interval: 0   Last Check: Sun Feb 17 12:14:33 2008
        Creator OS: 0
        Feature Compat: 1 backup-super
        Feature Incompat: 0 
        Tunefs Incomplete: 0 
        Feature RO compat: 0 
        Root Blknum: 513   System Dir Blknum: 514
        First Cluster Group Blknum: 256
        Block Size Bits: 12   Cluster Size Bits: 20
        Max Node Slots: 10
        Extended Attributes Inline Size: 0
        Label: /export/u01
        UUID: 1543E66DCDC14370B24351676B8E4ABF
        Hash: 0 (0x0)
        Cluster stack: classic o2cb
        Inode: 2   Mode: 00   Generation: 4081245430 (0xf342dcf6)
        FS Generation: 4081245430 (0xf342dcf6)
        CRC32: 00000000   ECC: 0000
        Type: Unknown   Attr: 0x0   Flags: Valid System Superblock 
        Dynamic Features: (0x0) 
        User: 0 (root)   Group: 0 (root)   Size: 0
        Links: 0   Clusters: 716800
        ctime: 0x47b895a9 -- Sun Feb 17 12:14:33 2008
        atime: 0x0 -- Wed Dec 31 16:00:00 1969
        mtime: 0x47b895a9 -- Sun Feb 17 12:14:33 2008
        dtime: 0x0 -- Wed Dec 31 16:00:00 1969
        ctime_nsec: 0x00000000 -- 0
        atime_nsec: 0x00000000 -- 0
        mtime_nsec: 0x00000000 -- 0
        Last Extblk: 0   Orphan Slot: 0
        Sub Alloc Slot: Global   Sub Alloc Bit: 65535

Also adding to bug 1255.