David, I thought I was going to stay quite and not say anything but all through the Holidays I couldn't get this email from my mind. I know you have done a lot of testing with LVS and I would like to get some of your benchmarks so that I can learn more about how the LVS behaves on Linux for s/390, so Could I get some of the benchmark numbers you have gotten from testing tunneling on Linux for s/390? It would really benefit me and my work with customers, so if you can send some of those numbers it would really help a lot of people. I am willing to send them to the LVS forum (which I belong to) and let them know how bad there performance is. As a matter of fact we have some people working with the LVS in production and by the way as much as your 8000 linux images running under VM customer is not a reference (and unknown to everyone) so is this customer and it is very happy with the performance. Please let me know when I can get your benchmark numbers. Thanks Carlos :-)
> If you use tunneling as the protocol the real servers can be > located any where and it supports windows or any other > operating system > that you can run the application and that supports TCPIP. > [... snip ...] > I > have tested > having servers in Linux zSeries and Intel and everything > worked fine. I > know I am over simplifying things but it is really not > difficult to setup > and test. Carlos :-) Doing this on a par with existing Unix or Windows based clustering tools is quite a bit harder than just workload distribution, which is the majority of what LVS can do -- LVS provides services similar to the external CSS boxes. To do more sophisticated clustering, it takes a LOT of hardware resources, and unfortunately, zSeries hardware is still more expensive than the commodity hardware on the discrete systems which makes this a hard sell as a viable solution. The tunneling you mention is *very* processor intensive -- exactly the point I mentioned earlier. Technically it works, but I don't think very many of us can dedicate an engine -- even a lower cost IFL engine -- to layer 2 frame forwarding, and in a significant implementation, it's not unlikely to need that kind of horsepower to keep packets moving. We need some hardware-based acceleration for this function, ASAP. -- db Saying goes: Great minds think alike - I say: Great minds think for themselves! Carlos A. Ordonez IBM Corporation Server Consolidation
