From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: Re: [PATCH] brd: Allow ramdisk to be allocated on selected NUMA node
To: Adam Manzanares <Adam.Manzanares@wdc.com>, Jens Axboe <axboe@kernel.dk>
Cc: "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
 Mel Gorman <mgorman@suse.com>, Hannes Reinecke <hare@suse.com>
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From: Hannes Reinecke <hare@suse.de>
Message-ID: <a1034506-b50a-40f8-eee2-d353448da2fd@suse.de>
Date: Fri, 15 Jun 2018 08:06:04 +0200
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On 06/14/2018 10:53 PM, Adam Manzanares wrote:
[ .. ]
>>>
>>> Then how about a numactl ... dd /dev/ram ... after the modprobe.
>>
>> Yes of course, or you could do that for every application that ends
>> up in the path of the doing IO to it. The point of the option is to
>> just make it explicit, and not have to either NUMA pin each task,
>> or prefill all possible pages.
>>
> 
> Makes sense, I have done some similar benchmarking and had to worry
> about NUMA awareness and the numactl + dd approach seemed to work
> because I wanted to not take a performance hit for page allocation
> during the benchmarking.
> 
> Would anyone be interested in forcing the allocations to occur during
> module initialization?
> 
YES.

Cheers,

Hannes