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Date: Fri, 07 Nov 2014 10:53:37 +0100
From: Richard Weinberger <richard@nod.at>
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Subject: Re: [PATCH] UBI: Block: Add blk-mq support
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Am 07.11.2014 um 10:46 schrieb Artem Bityutskiy:
> On Mon, 2014-11-03 at 09:23 +0100, Richard Weinberger wrote:
>> Am 03.11.2014 um 09:18 schrieb Christoph Hellwig:
>>> On Sun, Nov 02, 2014 at 02:00:55PM +0100, Richard Weinberger wrote:
>>>> +#define UBIBLOCK_SG_COUNT 64
>>>
>>>
>>> Can you document why you choose this number? The default nr_request
>>> for the old code would be 128.
>>
>> Is 64 a problem? Beside of the fact that I forgot to set blk_queue_max_segments().
>> I used this number because 128 seemed a bit high and my goal was to
>> keep the memory footprint small.
>> This is also why I've set tag_set.queue_depth to 64.
> 
> The request was to document, so lets' document the choice.

Of course I'll document it. But so far I had no time to do a
v2 of this patch.

Thanks,
//richard