Path: utzoo!attcan!uunet!husc6!uwvax!oddjob!ncar!ames!umd5!brl-adm!brl-smoke!gwyn
From: gwyn@brl-smoke.ARPA (Doug Gwyn )
Newsgroups: comp.bugs.sys5
Subject: Re: Is applying ulimit to pipes a bug?
Keywords: ulimit pipe filesystem
Message-ID: <7928@brl-smoke.ARPA>
Date: 19 May 88 11:13:45 GMT
References: <242@twg-ap.UUCP> <244@twg-ap.UUCP>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 19

In article <244@twg-ap.UUCP> dwh@twg-ap.UUCP (Dave Hamaker) writes:
>> If I don't raise the ulimit, the pipes fail.
>Oh embarrassment!  I had come to this conclusion because of past experiences
>and when I try it now, it doesn't fail.  The circumstantial evidence was
>overwhelming... but apparently quite wrong.  Something else may have been at
>work; I have no reason to suspect the operating system now.

Don't be so quick to retract this.  I have it on very good authority
that several important things break that shouldn't, once the user
has lowered ulimit to (say) 0.  I'm not sure that pipe writes are in
this category but it wouldn't surprise me.  I tried an experiment on
our Cray-2 and was rather startled at the form taken by the system
failure modes that this triggered.  I was afraid to try the experiment
that I really wanted to...

I urge all System V vendors to completely DISABLE ulimit, not just
because of this problem but because it is not a good solution to
whatever problem it was perceived as "fixing".  Its effects are far
too drastic for whatever valid use it might have had.