Re: [Alsa-user] new source of MIDI playback slow-down identified - 5a03b051ed87e72b959f32a86054e1142ac4cf55 thp: use compaction in kswapd for GFP_ATOMIC order > 0

[Arthur M. <art...@in...>]

Andrea Arcangeli wrote, on 23/02/11 02:45:
> On Tue, Feb 22, 2011 at 02:40:47PM +0100, Andrea Arcangeli wrote:
>>   	spin_lock_irq(&zone->lru_lock);
>>   	for (; low_pfn<  end_pfn; low_pfn++) {
>>   		struct page *page;
>> +
>> +		cond_resched();
>> +
>
> my bad, see the above spin_lock_irq oops...
>
> I attached two replacement patches to apply in order (both of them
> should be applied at the same time on top of git upstream, and they
> shouldn't lockup this time).

OK, these patches applied together against upstream didn't cause a crash 
but I did observe:

significant slowdowns of MIDI playback (moreso than in previous cases, 
and with less than 20 Meg of swap file in use);

kswapd0 sharing equal top place in CPU usage at times (e.g. 20 percent).

If I should try only one of the patches or something else entirely, 
please let me know.

Regards,

Arthur.