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Path: sserve!manuel!munnari.oz.au!uunet!gumby!destroyer!gatech!usenet.ins.cwru.edu!ljo
From: ljo@r2d2.eeap.cwru.edu (L. Jonas Olsson)
Newsgroups: comp.unix.bsd
Subject: Re: [386BSD] How can I expand data segment?
Date: 6 Oct 1992 15:27:50 GMT
Organization: Case Western Reserve Univ. Cleveland, Ohio (USA)
Lines: 31
Message-ID: <1asb9mINNcov@usenet.INS.CWRU.Edu>
References: <45240004@hpycla.kobe.hp.com> <veit.718359993@du9ds3>
NNTP-Posting-Host: proteus.eeap.cwru.edu

In article <veit.718359993@du9ds3> veit@du9ds3.uni-duisburg.de writes:
>In <45240004@hpycla.kobe.hp.com> yas@hpycla.kobe.hp.com (Yasuyuki Suzuki) writes:
>
>>I have 50MB of swap space on my 386BSD disk. But the data segment size
>>of each process seems to be limited around 4MB.
>
>>How can I expand data/stack/text segment size of each process?
>
>limit datasize unlimited
>limit stacksize unlimited
>

With the stock sources this will give you a 32MB limit on the data size,
for even more you need to edit /usr/src/sys.386bsd/i386/include/vmparam.h.
In this file you have the parameters for default data size (DFLDSIZ) and
max data size (MAXDSIZ) among others. I have them set to 16 and 128MB and
have successfuly used up to 45MB in one process. The system seems a little
more flaky though so some other tweaking/bug fixing might be needed. Also
note that the system grinds to a halt when the swap space is used up, there
is no friendly message "virtual memory exhausted" and the mallocs don't
return 0.
What kinds of paging are used/possible to use in 386BSD? There are options
in the config files for swappages, vnodepager, and devpager. Is the
vnodepager similar to Mach's inodepager? (Mach systems can page to empty
inodes on the regular partitions and does not need any swap partition)
Is it possible to get the vnodepager to do this?

Jonas Olsson
ljo@po.cwru.edu