[openib-general] Re: A new simple ulp (SPTS)

[Jeff Carr]

On 06/27/05 13:32, Michael S. Tsirkin wrote:
> Quoting r. Jeff Carr <jcarr at linuxmachines.com>:
> 
>>Here is an updated version and a simple perl script that tests it's
>>performance. With 2K messages, these were the performance numbers
>>between 2 systems (3.6ghz Xeon/w 133mhz/64bit pci).
>>
>>root at delta:~# ./fast_test.pl 20
>>starting sends
>>0 messages/sec (0 Mb/sec)
>>131072 messages/sec (2047 Mb/sec)
>>131072 messages/sec (2047 Mb/sec)
>>131072 messages/sec (2047 Mb/sec)
>>174762 messages/sec (2730 Mb/sec)
>>163840 messages/sec (2559 Mb/sec)
>>196608 messages/sec (3071 Mb/sec)
>>183500 messages/sec (2867 Mb/sec)
>>174762 messages/sec (2730 Mb/sec)
>>196618 messages/sec (3072 Mb/sec)
>>187254 messages/sec (2925 Mb/sec)
>>180232 messages/sec (2816 Mb/sec)
>>196616 messages/sec (3072 Mb/sec)
>>189333 messages/sec (2958 Mb/sec)
>>183507 messages/sec (2867 Mb/sec)
>>196614 messages/sec (3072 Mb/sec)
>>190656 messages/sec (2978 Mb/sec)
>>202571 messages/sec (3165 Mb/sec)
>>138785 messages/sec (2168 Mb/sec)
>>131075 messages/sec (2048 Mb/sec)
>>
>>Jeff
>>
> 
> 
> Does this mean the bandwidth is 200-300 MByte/sec?

Well, 3000 Mb/sec / 8 == 375 MB/sec :)

yes. It's not as fast as I would hope. I'm not sure what the cause is
yet. I think it's more to do with the small 2K message size.

If I run this test at 16/64KB message size it's likely to have better
performance. The PCI bus has theoretical throughput around 700MB/sec.

> What is the CPU utilization number (easy to sample with e.g. vstat)?

The CPU is maxed out in this code because it's set to spin while polling.

Jeff