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<div>I will push our vulkan guys to test it, their bo list is very long.<br>
<br>
<p dir="ltr" style="display:inline"><span style="color:#888888"><span style="font-size:0.81em">发自坚果 Pro</span></span></p>
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<div style="margin:0 0px; font-size:105%"><font color="#629140" style="line-height:1.4"><span>Christian K鰊ig <deathsimple@vodafone.de> 于 2017年8月28日 下午7:55写道：</span></font></div>
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<div class="PlainText">Am 28.08.2017 um 06:21 schrieb zhoucm1:<br>
><br>
><br>
> On 2017年08月27日 18:03, Christian König wrote:<br>
>> Am 25.08.2017 um 21:19 schrieb Christian König:<br>
>>> Am 25.08.2017 um 18:22 schrieb Marek Olšák:<br>
>>>> On Fri, Aug 25, 2017 at 3:00 PM, Christian König<br>
>>>> <deathsimple@vodafone.de> wrote:<br>
>>>>> Am 25.08.2017 um 12:32 schrieb zhoucm1:<br>
>>>>>><br>
>>>>>><br>
>>>>>> On 2017年08月25日 17:38, Christian König wrote:<br>
>>>>>>> From: Christian König <christian.koenig@amd.com><br>
>>>>>>><br>
>>>>>>> Add the IOCTL interface so that applications can allocate per VM <br>
>>>>>>> BOs.<br>
>>>>>>><br>
>>>>>>> Still WIP since not all corner cases are tested yet, but this <br>
>>>>>>> reduces<br>
>>>>>>> average<br>
>>>>>>> CS overhead for 10K BOs from 21ms down to 48us.<br>
>>>>>> Wow, cheers, eventually you get per vm bo to same reservation <br>
>>>>>> with PD/pts,<br>
>>>>>> indeed save a lot of bo list.<br>
>>>>><br>
>>>>> Don't cheer to loud yet, that is a completely constructed test case.<br>
>>>>><br>
>>>>> So far I wasn't able to archive any improvements with any real <br>
>>>>> game on this<br>
>>>>> with Mesa.<br>
> With thinking more, too many BOs share one reservation, which could <br>
> result in reservation lock often is busy, if eviction or destroy also <br>
> happens often in the meaning time, then which could effect VM update <br>
> and CS submission as well.<br>
<br>
That's exactly the reason why I've added code to the BO destroy path to <br>
avoid at least some of the problems. But yeah, that's only the tip of <br>
the iceberg of problems with that approach.<br>
<br>
> Anyway, this is very good start and try that we reduce CS overhead, <br>
> especially we've seen "reduces average CS overhead for 10K BOs from <br>
> 21ms down to 48us. ".<br>
<br>
Actually, it's not that good. See this is a completely build up test <br>
case on a kernel with lockdep and KASAN enabled.<br>
<br>
In reality we usually don't have so many BOs and so far I wasn't able to <br>
find much of an improvement in any real world testing.<br>
<br>
Regards,<br>
Christian.<br>
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