Subject: Re: heavy use of mmap() ?
To: None <current-users@NetBSD.ORG>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: current-users
Date: 04/30/1998 09:26:35
>>> I recall a discussion some time ago about heavy use of mmap()
>>> actually _decreasing_ performace of reads from mmap()ped files.
>> A while ago, NetBSD had a bug that meant that reads and writes via
>> mmap() and accessing the memory were decoupled from reads and writes
>> via read() and write().  [...]
> Well, so if the files would be only read (normal situation on Web
> server), everything would be okay ?

Right, provided nobody is trying to access the file via any means, I
know of nothing that causes any problem.  (I should have, but didn't,
say this when first replying - I know of nothing that causes
performance problems but not correctness problems when mixing read-only
mmap and read.)

Of course, it's entirely possible that such a bug exists and I just
don't know about it.  There's lots I don't know about.

					der Mouse

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