TCP Splicing with HAProxy 1.4.8

Hi,

I've been trying out HAProxy 1.4.8 on RHEL 6 beta (running kernel 2.6.32-44.1.el6.x86_64).

I created a very simple configuration with which I'd been testing with and without the "option splice-response" directive, but had seen no real performance improvement.

The cynic in me thought it might not be working, so I used strace to examine some requests/responses. Small transfers didn't seem to result in any splice() calls, but I did see a suitable number for a much larger transfer. (Though I did see a lot of splice() calls generating EAGAIN, which suggested that there was something not quite right).

Are there specific traffic profiles which benefit most from the use of splicing? As I mentioned earlier I'm not seeing any performance improvement while using it - in fact I've seen degradation when transferring large files, which suggests to me that I'm possibly not using it appropriately.

Any advice on using TCP splicing with HAProxy would be greatly appreciated.

Cheers,

Maurice Received on 2010/10/07 22:01