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Date: Mon, 12 Nov 2012 16:12:10 -0800
From: Julian Elischer <julian@freebsd.org>
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To: Adrian Chadd <adrian@freebsd.org>
Subject: Re: Memory reserves or lack thereof
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Cc: StevenSears <Steven.Sears@netapp.com>, Alan Cox <alc@rice.edu>,
 alc@freebsd.org, "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>,
 Sushanth Rai <sushanth_rai@yahoo.com>, pho@freebsd.org,
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On 11/12/12 3:49 PM, Adrian Chadd wrote:
> On 12 November 2012 15:26, Alan Cox <alc@rice.edu> wrote:
>> On 11/12/2012 5:24 PM, Adrian Chadd wrote:
>>> .. wait, so what exactly would the difference be between M_NOWAIT and
>>> M_WAITOK?
>>
>> Whether or not the allocation can sleep until memory becomes available.
> Ok, so we're still maintaining that particular behaviour. Cool.
                     no mem                  |     mem avail
----------------------------------------------
M_WAITOK | wait, then success   |    success           |
----------------------------------------------
M_NOWAIT |  returns failure        |    success          |
----------------------------------------------

the question is whether  the top left can ever fail for any other reason.
>
>
>
> Adrian
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