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Date: Mon, 09 Aug 2010 13:49:01 -0500
From: Michael Roth <mdroth@linux.vnet.ibm.com>
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Subject: Re: [Qemu-devel] Virtual memory question
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: qemu-devel@nongnu.org

On 08/09/2010 11:46 AM, Michael Roth wrote:
>
> 2) exec.c:file_ram_alloc() assumes you're allocating off a hugetlbfs and
> makes some system calls to get the block/hugepage size. A quick hack
> might be to comment out the following in exec.c:gethugepagesize():
>
> if (fs.f_type != HUGETLBFS_MAGIC)
> fprintf(stderr, "Warning: path not on HugeTLBFS: %s\n", path);
>
> You may also want to replace the mkstemp() with a mkostemp() and set
> O_SYNC on the file
>
> But beyond hacks, I think generalizing -mempath might have some other
> useful applications (using it as a way to expose tmpfs-backed/numactl'd
> files as numa nodes to guests came up in an earlier discussion, and
> memory compression via zram/compcache is another).
>

Actually I guess 2) isn't really an issue, thought was an error path but 
I was mistaken.

-Mike