Re: Beating a dead horse

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Wed, 25 Nov 2015 14:57:02 -0553.75
    From:        "William A. Mahaffey III" <wam%hiwaay.net@localhost>
    Message-ID:  <56561F54.5040207%hiwaay.net@localhost>


  |   f: 1886414256  67110912       RAID                     # (Cyl. 66578*- 
  | 1938020)

OK, 67110912 is a multiple of 2^11 (2048) which is just fine.
The size is a multiple of 2^4 (16) so that's OK too.

  |           128  7545656543      1  GPT part - NetBSD FFSv1/FFSv2

The 128 is what I was expecting, from the dk0 wedgeinfo, and that's
fine.  The size is weird, but I don't think should give a problen.
Greg will be able to say what happens when there's a partial stripe
left over at the end of a raidframe array.

If you do ever decide to redo things, I'd make that size be a mulltiple of
2048 too (maybe a multiple of 2048 - 128).  Wasting a couple of thousand
sectors (1 MB) won't hurt (and that's the max).


But overall I think your basic layout is fine, and there's no need to adjust 
that.  The one thing that you need to do (if you really need better
performance, rather than just think you should have it - that is, if you
need it enough to re-init the filesystem) would be to change the ffs block 
size, or change the raidframe stripe size, so standard size block I/O turns
into full size stripe I/O.

Doing that should improve performance.  Nothing else is likely to help.

kre