Date: Wed, 21 Apr 2004 18:40:09 -0700 (PDT) From: Matthew Dillon <dillon@apollo.backplane.com> To: Julian Elischer <julian@elischer.org> Cc: Stephan Uphoff <ups@tree.com> Subject: Re: how to flush out cache.? Message-ID: <200404220140.i3M1e9l9097495@apollo.backplane.com> References: <Pine.BSF.4.21.0404211813150.31770-100000@InterJet.elischer.org>
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:Actually what I'm looking for is
:"throw away clean data"
:
:I want to dump the cached version of a file so that I can force a reread
:of the disk.
MS_INVALIDATE doesn't do that.
madvise()'s MADV_FREE does what you want, BUT it does not currently
work (at least on 4.x or in DFly) on file-backed data, it only works
with anonymous memory. I believe that on some systems MADV_FREE does
what you expect, e.g. like on Solaris (though I am not 100% sure), so
it would not be far-fetched to go and implement it.
-Matt
Matthew Dillon
<dillon@backplane.com>
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