[linux-lvm] getting pe_start right

Phillip Susi psusi at cfl.rr.com
Tue May 10 14:28:18 UTC 2011

On 5/6/2011 11:21 AM, Mike Snitzer wrote:
> chances are lvm2's data_alignment_detection will shift the data start to
> the start of the next full stripe of the raid5.

That appears to be what was going on.  I found entries in lvm.conf to 
enable/disable autodetection of the raid stripe width and turned it off.

> You should be able to specify the old start with:
> --dataalignment 192k --dataalignmentoffset 0
> (--dataalignmentoffset 0 likely isn't needed, but it just overrides
> lvm2's data_alignment_offset detection if it just so happens that
> raid5 has alignment_offset!=0)

The command line switches did not appear to override the autodetection; 
I had to shut it off in the conf file.  Is this a bug?

More information about the linux-lvm mailing list