[Qemu-devel] Re: [PATCH] upgraded mmap patches

[Alexander E. Patrakov]

Magnus Damm wrote:

> Hi All,
> 
> I have just finished upgrading the CONFIG_MMU_MAP (aka mmap) patches
> written by Piotrek. I have only tested to build the code with
> --target-list=i386-softmmu and only on x86 hosts running Linux. I am
> able to run Win XP SP2 as guest both with and without mmap
> acceleration with the patch.
> 
> The changes are not many since the last release by Piotrek, I just
> made sure the code applied to CVS of today and yeah, I added some
> basic code to support quad-word memory access. It is totally untested
> and probably broken right now. Someone please look at part4 of the
> patch and verify that I read 32-bit words the right way.
> 
> Sorry PowerPC folks, no ppc host support yet. I will port up the ppc
> host patches after someone has fixed so ppc compiles cleanly...
> 
> The first three parts are simply upgraded versions of the files
> v1-part[1-3].patch.gz that Piotrek posted to the list around a month
> ago. Part4 contains changes by me.
> 
> Enjoy, please report back to the list with problems and benchmarks!

Is a new patched qemu really supposed to be much slower than the original in
the case when /proc/sys/vm/max_map_count doesn't contain a number that's
big enough to enable acceleration?

-- 
Alexander E. Patrakov