[ofa-general] SRP/mlx4 interrupts throttling performance

[Cameron Harr]

Vladislav Bolkhovitin wrote:
> Cameron Harr wrote:
>>>>> Also, as I mentioned before, my time is going to be fairly limited 
>>>>> for a while, but I'll try to squeeze this in and will make sure I 
>>>>> run for longer periods of time. I'll also try to calculate an 
>>>>> exact end number based on iop/runtime.
>>>>>> Which backstorage do you use for BLOCKIO?
>>>>> Fusion IO ioDrive. I generally use 1 or 2, but somtimes up to 4 at 
>>>>> a time.
>>>> It might be a reason of not stable results. Can you try with NULLIO 
>>>> to narrow things down a bit?
>>
>> I actually tested NULLIO a while back at Vu's suggestion, but I 
>> believe I forgot to report on it. From my recollection, NULLIO gave 
>> me pretty consistent block sizes of 512B, which is the BS I used in 
>> the benchmark.
>
> Were the IOPS, CS and IRQ rates results stable and consistent between 
> runs?

I don't remember about the IOPs, but CS and IRQ rates were stable. 
However, they've also become stable in my later runs with 
scst_threads=[123].
>
> Anyway, try with the latest code. There are noticeable changes there.
>
> BTW, since you use the solid state media, you don't need any IO 
> scheduler. Hence, noop should be the best choice for you.
noop is what I've been running for the past while, before switching to 
deadline yesterday.