🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: comp.bugs.sys5
Article #137

Re: fork fail (Altos System V)

#137
From: Brandon S. Allbery
Date: Mon, 23 Oct 1989 13:05
36 lines
2089 bytes
In <3864@altos86.Altos.COM>, jerry@altos86.UUCP claims:
+---------------
| In article <506@oglvee.UUCP> jr@oglvee.UUCP (Jim Rosenberg) writes:
| >it fail on a request to get only 1 page unless I'm out of swap space?  (Which
| >I'm not.  We're getting these with many many thousand blocks of free swap
| >space -- we have a swap(1) which will show these.)
| 
| >Is there a tunable parameter that will rescue me here?  
| 
| Not really.  You really are running out of swap space.  Even though
| "swap -l" may  show plenty of swap space remaining, it is misleading.
| 
| UNIX allocates swap space for the entire .data and .bss regions whenever
| a process is exec'ed.  Even though swap -l shows plenty of swap space 
| available, most of the swap space is allocated to processes, which, although
| they may not currently be swapped out, still tie up the swap space.
+---------------

Something in your explanation does not match reality.

(a) On a system with 8MB RAM, 25776 blocks swap, 436 blocks reported "in use"
    by /etc/swap -l, I have observed "fork failed" and getcpages messages.
    This seems unlikely by your explanation.

(b) On a system with 8MB RAM and a "standard" swap space (12880 blocks), the
    system shouldn't page at all unless you run programs with more text than
    data/bss.  But they *do* page.

Kindly explain these.

++Brandon
-- 
-=> Brandon S. Allbery @ telotech, inc.   (I do not speak for telotech.) <=-
Any comp.sources.misc postings sent to this address will be DISCARDED -- use
allbery@uunet.UU.NET instead. My boss doesn't pay me to moderate newsgroups.
** allbery@NCoast.ORG ** uunet!hal.cwru.edu!ncoast!{allbery,telotech!bsa} **
Technical Details
Message-ID: <1989Oct23.130529.7828@telotech.uucp>
Path: arc1-ca.pugleaf.net!utzoo!attcan!utgpu!utstat!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!uc!nic.MR.NET!hal!ncoast!telotech!bsa

Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!attcan!utgpu!utstat!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!uc!nic.MR.NET!hal!ncoast!telotech!bsa
From: bsa@telotech.uucp (Brandon S. Allbery)
Newsgroups: comp.bugs.sys5
Subject: Re: fork fail (Altos System V)
Message-ID: <1989Oct23.130529.7828@telotech.uucp>
Date: 23 Oct 89 13:05:29 GMT
Distribution: na
Organization: Telotech, Inc.
Lines: 36