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Date: Tue, 10 Jun 2014 10:56:42 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v4 18/29] hostmem: add file-based
	HostMemoryBackend
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To: Hu Tao <hutao@cn.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>, Igor Mammedov <imammedo@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>, qemu-devel@nongnu.org, Eduardo Habkost <ehabkost@redhat.com>

Il 10/06/2014 10:30, Hu Tao ha scritto:
> On Tue, Jun 10, 2014 at 01:09:32AM -0400, Paolo Bonzini wrote:
>>
>>>>> +#define TYPE_MEMORY_BACKEND_FILE "memory-backend-file"
>>>> how about naming it after what it really is? "memory-backend-hugepage"
>>>> Later we could split it into generic superclass mmap-ed
>>>> "memory-backend-file" and have TPH specific code moved into this backend.
>>>
>>> OK.
>>
>> Actually I don't think there's anything hugepage-specific in this backend
>> (except perhaps passing a path instead of a filename).  It could be used
>> with a tmpfs backing storage like /dev/shm.
>
> What's the point compared to memory-backend-ram?

That you can use shared memory, for example together with vhost-user.

> Igor suggested memory-backend-file be compiled only for Linux. Does this mean
> memory-backend-file shuold be compiled also for systems supporting tmpfs
> or like?

Yes, I think it should be compiled on all POSIX systems.  But it can be 
done later.

Paolo