From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Arne H. Juul" To: gas2@cygnus.com, raeburn@cygnus.com Cc: bfd@cygnus.com Subject: Re: mmap changes, mostly for aout right now Date: Tue, 07 Nov 1995 17:10:00 -0000 Message-id: <9511080110.AA22833@datter.pvv.unit.no> X-SW-Source: 1995/msg00189.html > I've just checked in now some changes to bfd to use mmap for reading > files under certain circumstances. A snapshot file should be available > within the next hour or so. Please try it out and let me know of any > problems. [...] > Under NetBSD (on i386), I saw no significant change in CPU time used > (though my test case was different -- many more small files in and out of > libraries). [...] Unless I'm very mistaken, using mmap is currently a *very* bad idea on NetBSD. The buffer cache and VM system hasn't been merged, and this leads to lots of trouble when using mmap(), at least on NFS-mounted filesystems - the file as seen by read/write can be wildly different from the mmap view. This will (hopefully) change later on, but currently using mmap() on NetBSD in other than very carefully controlled circumstances will probably lead to disaster. - Arne H. J.