[openib-general] How about ib_send_page() ?

[Jeff Carr]

Grant Grundler wrote:

>>root at jcarr:/# dd if=/dev/shm/test of=/dev/null bs=4K
>>196608+0 records in
>>196608+0 records out
>>805306368 bytes transferred in 0.628504 seconds (1281306571 bytes/sec)
> 
> 
> Yeah. Sounds like there is. Should be able to do several GB/s like that.
> 
> I suppose it's possibly an issue with the Memory controller too.
> ZX1 interleaves accesses across 4 DIMMs to get the memory bandwidth.
> Might check to make sure your box is "optimally" configured too.
> 
> grundler at iota$ dd if=/dev/shm/test of=/dev/null bs=4K
> dd: opening `/dev/shm/test': No such file or directory

I just did dd if=/dev/zero of=test bs=1M count=768
I assume that the speed would be the same if there was non-zero data :)

I only have 2GB of ram.

> Sorry - what do I need to do to create /dev/shm/test?
> 
> I should probably "cheat" and use 16KB block since that
> is the native page size on ia64.

"cheating" in that sense is good. 16KB blocks will probably increase the 
performance a lot. I was even thinking I would try to do that on my Xeon 
system. (I don't know if that's possible.)

Jeff