Subject: Re: VPS mailing list, BSD interest?
To: Jason Thorpe <>
From: James Graham <>
List: tech-kern
Date: 10/01/1996 12:43:23
Jason Thorpe sez:
#  [Poul-Henning Camp sez]:
#  > There is no significant difference between the FDISK, bsd-disklabel,
#  > mirror, stripeing and raid 5 operations.  They all translate a
#  > (dev+blkno+len) tupple to one or more similar tupples.

1.  Minor nit:  (x+y+z) is a triple, not a tuple.

2.  There is no difference between the operations?  You've obviously
    not dealt with a RAID5 filesystem before.  Nice idea, but you pay
    for it with performance.  And yes, I consider performance significant.
The first time I ran the ccdconfig thing and tried to newfs it,
I ended up running it on unevenly sized filesystems (OK) with an
interleave of 1 (NOT OK!).  Boy, was THAT _slow_!  Not to mention
I wanted concatenation anyway... :-)

I haven't had the opportunity to stripe or mirror a filesystem yet
(insufficient disk space and differently-sized disks make this a
bit of a challenge), so I can't comment on performance.  But it's nice
to have the concatenation as when I partitioned my disks, I had one piddly
partition of 70MB left over.  Seeing as that wasn't really enough with
which to do jack, I concatenated it to my user disk.

# Jason R. Thorpe                             
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