Did you actually have a problem with your filesystem?
The logstart is in an "fsb" which is actually an encoded number, which
must be decoded back into a disk address, see XFS_FSB_TO_DADDR. So
unless you saw an actual problem, I think your log is in the right
place, and it just looks odd, because the logstart fsb is not related to
a disk address.
-Eric
On Wed, 2004-06-09 at 07:26, Oleg Zozulya wrote:
> I've tried mkfs.xfs (version 1.3.1) on a partition with 8401932 sectors
> (512 bytes). The default options resulted in:
>
> meta-data=/dev/hdd1 isize=256 agcount=8, agsize=131280
> blks
> = sectsz=512
> data = bsize=4096 blocks=1050240, imaxpct=25
> = sunit=0 swidth=0 blks, unwritten=1
> naming =version 2 bsize=4096
> log =internal log bsize=4096 blocks=2560, start=1048580
> =version=1 sectsz=512 sunit=0 blks
> realtime =none extsz=65536 blocks=0, rtextents=0
>
> One can notice incorrect inline log position: logstart + logblocks >
> dblocks, i.e.log end is out of xfs partition.
>
> However xfs_logprint gives the correct real position in the middle of
> the partition:
>
> data device: 0x1641
> log device: 0x1641 daddr: 4200992 length: 20480
>
> I searched the xfs_mkfs.c for default logstart:
>
> logstart=XFS_AGB_TO_FSB(mp,logagno,XFS_PREALLOC_BLOCKS(mp))
> in my case logagno = 4
>
> where in macro:
>
> #define XFS_AGB_TO_FSB(mp,agno,agbno) \
> (((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
>
> agblklog is the rounded up log of agblocks! The rounding do cause the
> log position mislead when the agblocks is not a power of 2.
>
> The macro should be smth like:
>
> #define XFS_AGB_TO_FSB(mp,agno,agbno) \
> (((xfs_fsblock_t)((agno)*(mp)->m_sb.sb_agblocks)) | (agbno))
>
> Sincerely,
> Oleg Zozulya
> Acronis Ltd.
--
Eric Sandeen [C]XFS for Linux http://oss.sgi.com/projects/xfs
sandeen@xxxxxxx SGI, Inc. 651-683-3102
|