Date: Mon, 4 Sep 1995 16:39:27 +0800 (WST) From: Peter Wemm <peter@haywire.DIALix.COM> To: Brian Tao <taob@gate.sinica.edu.tw> Cc: dillon@best.com, freebsd-chat@freebsd.org Subject: Re: FreeBSD vs. BSD/OS disk performance Message-ID: <Pine.SV4.3.91.950904162647.22505F-100000@haywire.DIALix.COM> In-Reply-To: <Pine.BSI.3.91.950904161104.3917E-100000@aries>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, 4 Sep 1995, Brian Tao wrote:
> On 29 Aug 1995, Peter Wemm wrote:
> >
> > Didn't Matt Dillon mention that his Disk IO comparisons between BSD/OS
> > and FreeBSD that showed that FreeBSD wiped the floor with BSD/OS? And
> > didn't somebody from UUNET suggest he was mistaken and challenge him
> > to post numbers, to which Matt responded by posting some benchmarks
> > showing something like a 5-times improvement?
>
> I'd *love* to see these numbers. BSD/OS used to only support the
> Buslogics controllers, and recently added NCR support, but I don't
> know how good it is. Probably still can't use the Adaptec 2940/3940
> controllers.
I didn't pay much attention when it was first posted, but I remember
thinking that it sounded like BSD/OS wasn't doing clustering properly,
and was seriously suffering as a result.
I know the newfs/mkfs/tunefs settings make a big difference to FreeBSD..
Performance is pretty lousy if the filesystem has the older-style
rotational block layout where the blocks are not contiguous.
I redid a mkfs on the box next to me, and saw a performance boost from
about 600K/sec to about 3.0MB/sec - and that was on an old, slowish seagate
disk.. :-)
The thing I wonder though, is if that would make much difference to a
news filesystem.. Raw throughput is not the issue, it's more a problem
of head seek latency, and reducing the delays caused by doing sync inode
and directory updates. FreeBSD-current can now turn off the sync inode
updates, but FreeBSD doesn't have a trickle buffer update like SVR3, SVR4
and Linux do, so it's a little risky to defer your inode updates to a
flurry of updates every 30 seconds. And, of course, turning off the sync
inode updates removes a syncronous access time update each time a file is
read from your news spool by a reader/nntpd/nfs access.
Cheers,
-Peter
> --
> Brian ("Though this be madness, yet there is method in't") Tao
> taob@gate.sinica.edu.tw <-- work ........ play --> taob@io.org
>
>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.SV4.3.91.950904162647.22505F-100000>