[ofa-general] SRP/mlx4 interrupts throttling performance

[Vladislav Bolkhovitin]

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?

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.