Re: [Scst-devel] Performance issue

[Vladislav B. <vs...@vl...>]

Knister, Aaron S. (GSFC-606.2)[COMPUTER SCIENCE CORP] wrote on 02/16/2017 10:27 AM:
> Hi Everyone,
> 
> I'm attempting to build an FC to IB gateway that will export FC storage targets from a
> DDN SFA12K to various clients using SRP. I'm using the pass through disk handler to
> export the targets and functionally it works and appears stable. The problem I'm having
> is low performance. Using the disk perf handler the clients can saturate the scst srp
> target (3.2GB/s). The SCST host itself can push 3.2GB/s to/from the FC HBA (basic test
> using dd and watching counters in the DDN). However when I put the two together I
> struggle to get even half of that performance. I see peaks of roughly 3.2GB/s if I say
> tweak some thread settings in Scst and I/O momentarily backs up. I'm stumped. It feels
> like I'm missing a parameter that would open the proverbial flood gates but I can't
> find it. Does anyone have any suggestions? 

I'm not sure I understand the issue. Can you elaborate more of what _exactly_ you see?

Vlad