Re: Clearing the I/O caches? (for benchmark tests)

Tom M. Kroeger (tmk@cse.ucsc.edu)
16 Jul 1999 16:42:01 -0700

"Stephen C. Tweedie" <sct@redhat.com> writes:
>
> That's fine. The one thing it will _not_ do is clear out cached pages
> which are still referenced by the virtual memory system. Flushing
> memory by trying to allocate lots will try to swap that memory out too.
> Remember, any running binaries or in-use libraries will have pages
> mapped into some process's address space, so just going through the
> cache won't get rid of those pages: you'll have to unmap them first by
> passing through the swapper too.

This explains why hogging memory was able to cause more cache misses than
a freshly booted machine.

-- 


                       tmk


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