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From: ballard@ucs.ubc.ca (Alan Ballard)
Newsgroups: comp.os.os2.misc
Subject: Re: Virtual Memory Page Size
Message-ID: <1991May17.171113.11939@unixg.ubc.ca>
Date: 17 May 91 17:11:13 GMT
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In article <9645@cognos.UUCP> bradc@cognos.UUCP () writes:
>Is the virtual memory page size (ie. the unit of swapping) adjustable
>under OS/2 (version 1.3) or is it some fixed size such as 64K?

OS/2 1.x uses SEGMENTED, not paged, virtual memory.  The pieces
swapped are the code and data segments as defined by the applications.
Using a larger number of smaller data segments might help. 

Actually, code segments aren't supposed to get swapped, they should be just 
reloaded from disk as needed, though this may not have worked until
1.3.  Smaller code segments will help reduce the disk activity 
needed to reload them, however. 
 
OS/2 2.0 is a PAGED system. Anyone know what the page size is?

>We are trying to reduce the page size in an attempt to improve virtual
>memory performance.

Are you running 1.3, which considerably improved memory performance?
Do you have the right MEMMAN options specified in config.sys 
(SWAP,MOVE,SWAPDOS)


-- 
Alan Ballard                   | Internet: ballard@ucs.ubc.ca
University Computing Services  |   Bitnet: USERAB1@UBCMTSG
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