[openib-general] Re: user-mode verbs on Itanium

[Michael S. Tsirkin]

Quoting r. Grant Grundler <iod00d at hp.com>:
> Subject: Re: user-mode verbs on Itanium
>
> The first sample (611) on the client is improbably small for a 1.5Ghz
> system (i.e ~0.4 usecs).  That is a clue that delta[0] means
> something different than delta[{N>0}] on the client.
> It might be accurate if the client sends first and the next cycle count
> is taken right after telling the card data is ready to send.
> This could be useful data too.
> 
> Michael (mst), is it obvious to you if I've understood that correctly?
> Either way, I'd like to leave the test as is and add the explanation
> to the README.

Actually, the test had a bug - results were stored in
tstamp[1]...tstamp[1001] instead of tstamp[0]...tstam[999].

Your patch initialized tstamp[0] to get_clock which still isnt right
since its take before post_send and not after that.

revision 2279 fixes this by storing the clock in tstamp[scnt - 1].

Thanks!
MST

-- 
MST - Michael S. Tsirkin