On Sun, 17 Jun 2007, Wakko Warner wrote: > dean gaudet wrote: > > On Sat, 16 Jun 2007, Wakko Warner wrote: > > > > > When I've had an unclean shutdown on one of my systems (10x 50gb raid5) it's > > > always slowed the system down when booting up. Quite significantly I must > > > say. I wait until I can login and change the rebuild max speed to slow it > > > down while I'm using it. But that is another thing. > > > > i use an external write-intent bitmap on a raid1 to avoid this... you > > could use internal bitmap but that slows down i/o too much for my tastes. > > i also use an external xfs journal for the same reason. 2 disk raid1 for > > root/journal/bitmap, N disk raid5 for bulk storage. no spindles in > > common. > > I must remember this if I have to rebuild the array. Although I'm > considering moving to a hardware raid solution when I upgrade my storage. you can do it without a rebuild -- that's in fact how i did it the first time. to add an external bitmap: mdadm --grow --bitmap /bitmapfile /dev/mdX plus add "bitmap=/bitmapfile" to mdadm.conf... as in: ARRAY /dev/md4 bitmap=/bitmap.md4 UUID=dbc3be0b:b5853930:a02e038c:13ba8cdc you can also easily move an ext3 journal to an external journal with tune2fs (see man page). if you use XFS it's a bit more of a challenge to convert from internal to external, but see this thread: http://marc.theaimsgroup.com/?l=linux-xfs&m=106929781232520&w=2 i found that i had to do "sb 1", "sb 2", ..., "sb N" for all sb rather than just the "sb 0" that email instructed me to do. -dean - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
