From owner-freebsd-hackers  Sat Mar  8 23:20:54 1997
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Date: Sun, 9 Mar 1997 02:20:26 -0500 (EST)
From: Brian Tao <taob@risc.org>
Reply-To: Brian Tao <taob@risc.org>
To: Marc Slemko <marcs@znep.com>
cc: "matthew c. mead" <mmead@goof.com>, isp@freebsd.org, hackers@freebsd.org
Subject: Re: freebsd as a news server?
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On Sat, 8 Mar 1997, Marc Slemko wrote:
> 
> #!/usr/bin/perl
> for ($i = 0; $i < 1000; $i++) {
>         open(F, ">test.$i");
>         close F;
> }
> for ($i = 0; $i < 1000; $i++) {
>         unlink("test.$i");
> }
>
> This gives me 36.62 seconds sync and a drive that sounds like it is
> trying to chew on a pengiun vs. 22.99 async and an almost silent
> drive.

    I was quite sure the difference was much greater, so I tried it on
my system at home after seeing your numbers:

# mount -u -o async,noatime /
# cd /tmp ; time touch `jot 1000` ; time rm `jot 1000`
0.055u 1.452s 0:01.55 96.7% 17+186k 1+24io 0pf+0w
0.062u 0.371s 0:01.10 39.0% 175+244k 0+23io 0pf+0w
# sync
# mount -u /
# time touch `jot 1000` ; time rm `jot 1000`
0.062u 1.655s 0:34.51 4.9% 16+183k 0+2023io 0pf+0w
0.047u 0.618s 0:30.19 2.1% 178+242k 0+2000io 0pf+0w

    2.65s vs. 64.70s in tcsh, and 1.72s vs. 44.44s using your perl
example.  Why the large discrepancy in async times, I wonder?
--
Brian Tao (BT300, taob@risc.org)
"Though this be madness, yet there is method in't"