I run a setup like this now, although on Linux. If you have a pro license, there is no special setup required for dual-core or multiple CPUs. A single pro server will use all available processors. You can also install multiple pro server instances on each machine and both will use all processes. There is a Pro config guide somewhere on Witango's site.
I did performance tests with the 5.5 pro app server a while back, all on Linux. Some were on 2-way Hyper-Threaded servers. Some were on 2-way dual core Opteron servers. The goal was to determine the configuration that yielded the highest number of simulated concurrent users with all requests completing in 10 seconds or less. I use apache JMeter for this testing. I found that having HyperThreading turned on helped a little. IIRC, ~15% more simulated users than with HT off. If you are using an old version of Linux (2.4 kernel), or Windows (? prior to release of HT CPUs), it is highly likely that HT will slow things down because the OS does not properly take advantage of HT. I found that changing PROCESSAFFINITY to be anything but ALL caused a major slow-down. This could be specific to Linux, as this tweak seems dependent on the kernel's scheduling. The 5.5 server handles threads nicely, and a single app server instance will make full use of dual-core and multiple CPU hardware. I found no significant difference in performance/capacity between running a single app server per box vs. two app servers per box. I use two app servers per box in production, for two reasons. One, I think there could be corner cases where a larger thread pool could help, like a wave of traffic hitting all at once. Two (and more importantly), when an app server gets bit by the !CST bug, or other code problem that causes it to crash, it affects 1/2 the users it would have if I used one instance per box. The drawback is that two app servers per box take a bit more work to setup -- more config files, log files, init scripts, etc. If you setup the Witango client to use more than two app server instances, you may need an updated version of the client module. I discovered a bug last Fall where the client would only send requests to two app servers, even when configured with more than two. The bug was fixed by Witango Tech., but I'm not sure if that fix is in the latest release of the 5.5 server or not. I recommend testing everything, including performance tests. Performance testing is the only way to know what you're getting for your efforts. Your tests may yield very different results from mine, due to Windows vs. Linux, and/or application code differences. You may even find some bottlenecks in your code. Finally, Robert Shubert does consulting for this sort of setup. He was very helpful narrowing down the Witango client bug. - Jeff At 3:30 PM -0400 08/02/2006, Wolf, Gene wrote: > Thanks Robert. I will check out the Witango site to find any messages I can > for setting this up but it seems to me with dual core CPU's becoming > commonplace and now multiple dual cores being readily available, it would be > very useful for Witango to provide specific instructions on how to set up 1, > 2 and 4 CPU boxes or single and dual core cpu's and also how to set up > multiple boxes to take best advantage of the cpu's. It seems really > unreasonable to expect someone new to Witango to have to pour through the > Witango mail list archives to figure out how to do this. > >-----Original Message----- >From: Robert Garcia [mailto:[EMAIL PROTECTED] >Sent: Wednesday, August 02, 2006 3:00 PM >To: [email protected] >Subject: Re: Witango-Talk: Setting up multiple Witango boxes > >I missed the last line, after the image, if you have professional licenses, >you should be able to use dual core on each, with will give you a load group >of 4 witango servers, and so you will have to have the 2 on the same servers, >point to different ports, which makes it a bit trickier, but doable. Unless >the professional license will allow you to set processor affinity to ALL, then >you will have just 2 witango servers, taking advantage of all cores, which, >IMHO, would be the best setup. > > >-- > >Robert Garcia >President - BigHead Technology >VP Application Development - eventpix.com >13653 West Park Dr >Magalia, Ca 95954 >ph: 530.645.4040 x222 fax: 530.645.4040 ><mailto:[EMAIL PROTECTED]>[EMAIL PROTECTED] - <mailto:[EMAIL PROTECTED]>[EMAIL >PROTECTED] ><http://bighead.net>http://bighead.net/ - ><http://eventpix.com>http://eventpix.com/ > >On Aug 2, 2006, at 11:50 AM, Wolf, Gene wrote: > >>I know a number of you have done this but I can't seem to find any >>instructions on doing this anywhere. We are outstripping our current hardware >>as we grow and slowly transition to another language. We need to gain >>capacity for processing Witango queries and plan on getting two new servers, >>dual core, strictly for processing Witango requests. I have two questions: >> >> 1. Can Witango currently take advantage of dual core processors and >> 2. Are there instructions anywhere that someone can point me to explaining >> how to set up an environment similar to the following: >> >><2006-08-02_14-43-44-069.png> >> >> >> If anyone can direct me to instructions, and offer pitfalls to watch out >> for I'd greatly appreciate it. Thanks! >> >> Oh, we will be using Witango 5.5 professional on each Windows server box. >> Yes, we're planning on purchasing 2 additional licenses. *grins* >> > >________________________________________________________________________ >TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > > >________________________________________________________________________ >TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf -- Jeff Bohmer VisionLink, Inc. ________________________________________________________________________ TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf
