[LTP] [PATCH] cpuset_memory_spread: change lowerlimit to 5000kb

[Hongchen Zhang]

Hi Martin,

On 2023/6/16 pm 5:31, Martin Doucha wrote:
> On 16. 06. 23 4:10, Hongchen Zhang wrote:
>> Hi Martin,
>>
>> On 2023/6/15 pm 10:27, Martin Doucha wrote:
>>> Hi,
>>>
>>> On 09. 06. 23 3:27, Hongchen Zhang wrote:
>>>> When I test the cpuset_memory_spread case,this case FAIL too often.
>>>> After dig into the code, I find out that the fowlloing things trigger
>>>> the FAIL:
>>>> 1) random events,the probability is very small and can be ignored
>>>> 2) get_meminfo which before send signal to test_pid
>>>> 3) account_memsinfo before result_check
>>>>
>>>> About 2) and 3), we can increase the value of lowerlimit to keep
>>>> the result as SUCCESS.After my testing, 5000kb is a reasonable value.
>>>
>>> we're also seeing these failures but only on architectures like 
>>> PowerPC with pagesize higher than the usual 4KB. On which 
>>> architectures do you see failures and what's the pagesize there?
>> I test on 3C5000+7A2000 machine, the architecture is LoongArch.The 
>> pagesize we used is 16KB.
> 
> So the underlying cause is the same - higher pagesize. That means the 
> upperlimit, lowerlimit and DATAFILE size should be calculated from 
> pagesize instead.IMO,upperlimit and DATAFILE size will not affect the result.
Change the lowerlimit like following?
lowerlimit = 2000kb*get_pagesize()/SIZE_4K;
But I have no idea which formula can we use.
Any suggestion?
> 

Best Regards
Hongchen Zhang