*BSD News Article 9128


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From: wilko@russia.idca.tds.philips.nl (Wilko Bulte)
Newsgroups: comp.sys.sun.admin,comp.unix.bsd
Subject: Increasing the buffer cache: how?
Message-ID: <375@apdnmi.idca.tds.philips.nl>
Date: 19 Dec 92 11:20:55 GMT
Sender: news@idca.tds.philips.nl
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I am currently trying to convince a Sun2 running Sunos 3.5 that it should
use more memory for the buffercache. Using adb, I have changed the nbuf
paramater in /vmunix.

This works insofar that the boot message indicates the new value. What
I don't understand is that the # of bytes reported as being used by the
buffer cache does not change. 

Eg a value of 64 in nbuf gives the same # of bytes as 112 in nbuf (both
using 575488 bytes).

This is something I don't understand. In SysV NBUF gives the number of
buffers, and each buffer has the same size as the disk block used on 
the particular filesystem type. A different parameter NHBUF gives the
number of hashbuffers.

Maybe this has something to do with the BSD filesys?

Please help to solve my ignorance ;-)

Wilko

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