Greetings,
I'm testing out XFS on some LVM2 volumes. These test volumes/FSs were
created with the simplest invocation of mkfs I could muster: 'mkfs -t xfs
/dev/vg0/lv0'. Now I'm getting some warnings from device-mapper which
(apparently) indicate that I need to use the new XFS log format and set up
my filesystems so that log writes are aligned properly.
I asked on linux-lvm, but it seems that list isn't stocked with XFS gurus
;), so I'm having a hard time figuring out to what I need to set my su
suboption at mkfs time (as in 'mkfs -t xfs -l internal,version=2,su=X
/dev/vg0/lv0'). I'm not quite understanding the interactions between
device-mapper, the device (or, in this case, LV) block size, and the
filesystem block size.
One suggestion I did get on linux-lvm goes like this:
> To me it looks like you should set su to your block size, so if your
> block size is 4k set su=8. I don't use xfs myself, so you may want to
> wait for confirmation before trying this.
Does that sound correct? Does anyone have the time or inclination to
explain this so I can understand what's going on, rather than just dropping
a value into my command (though that'd be appreciated, too)? Maybe this is
easy, and I'm just slow :)
Please cc: replies to me, as I am not subscribed to this list.
Manuel Gomez
|