Re: Re: [PATCH] raid5:Only move IO_THRESHOLD stripes from delay_list to hold_list in raid5_activate_delayed().

[majianpeng <majianpeng@gmail.com>]

On 2012-07-06 20:56 Paul Menzel <paulepanter@users.sourceforge.net> Wrote:
>Dear Ma Jian,
>
>
>thanks for the patch.
>
>
>Am Freitag, den 06.07.2012, 20:38 +0800 schrieb majianpeng:
>> To imporve write performance and as posssible as to achieve full-write,
>
>s,imporve,improve,
>s,posssible,possible,
>
>The second part of the sentence is not clear to me.
>
>Maybe: … and to achieve full-write if possible.
>
>> it only fetch IO_THRESHOLD stripes from delay_list to hold_list.
>
>Can you proof the speed up with some benchmarks? That would be awesome.
Yes, I will do 
>
>> Signed-off-by: majianpeng <majianpeng@gmail.com>
>
>Last not least, could you write your first and last names separated by a
>space? (I do not know if I separated them correctly.)
>
>Ma Jian Peng (马建朋) <majianpeng@gmail.com>
>
>    $ git config user.name "Ma Jian Peng (马建朋)"
>
Thanks, I will accecpt it.
>Maybe even pass `--global` to it.
>
>> ---
>>  drivers/md/raid5.c |    3 +++
>>  1 files changed, 3 insertions(+), 0 deletions(-)
>> 
>> diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
>> index 04348d7..45308c5 100644
>> --- a/drivers/md/raid5.c
>> +++ b/drivers/md/raid5.c
>> @@ -3662,6 +3662,7 @@ finish:
>>  
>>  static void raid5_activate_delayed(struct r5conf *conf)
>>  {
>> +	int count = 0;
>>  	if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) {
>>  		while (!list_empty(&conf->delayed_list)) {
>>  			struct list_head *l = conf->delayed_list.next;
>> @@ -3672,6 +3673,8 @@ static void raid5_activate_delayed(struct r5conf *conf)
>>  			if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
>>  				atomic_inc(&conf->preread_active_stripes);
>>  			list_add_tail(&sh->lru, &conf->hold_list);
>> +			if (count++ >= IO_THRESHOLD)
>> +				break;
>>  		}
>>  	}
>>  }
>
>
>Thanks,
>
>Paul
>