Thanks Andre and sorry for not mentioning about the other content that are actually requested by http get's from the jsp served., There is quite a lot of ajax calls and static content and that can be served out of httpd, but as of now it is not. I know not the best way, so i assume i have to increment my thread count correspondingly..
While planning to threads on a single node, do i have to take into account the failure scenario where say all other 4 nodes fail and just this one node has to serve out the entire web app load. For that, do i have to provision the thread count as many as 4 times what i arrive for a single node ? Your thoughts? On Sat, May 4, 2013 at 7:07 AM, André Warnier <a...@ice-sa.com> wrote: > yogesh hingmire wrote: > >> While planning / designing to build a web app that must scale to 2000 >> concurrent users, distributed across 5 Tomcat nodes in a cluster, Apache >> at >> the front of course and the ability to serve 20 concurrent requests per >> seconds during business hours, with a page response time of 5 seconds, how >> would we go about the ask ? What Apache / Tomcat / System (CPU/JVM) >> parameters should be considered for this design ? >> >> > I will provide the ABC, and leave the details for someone else. > You have 20 requests arriving per second, and it takes 5 seconds to > process one request and return the response. > So, over time, it will look like this > > Time new requests requests in-process requests terminated > > 0 20 20 0 > +1s 20 40 0 > +2s 20 60 0 > +3s 20 80 0 > +4s 20 100 0 > +5s 20 100 20 > +6s 20 100 40 > +7s 20 100 60 > etc... > > So, in principle, and assuming nothing else is going on, you need 100 > concurrent threads in Tomcat to process these requests. > (I would take a healthy margin of security and double that). > Whether for that you need a cluster of Tomcats is another discussion. > And how much memory you need to allocate to your Tomcat(s) JVM(s) is a > function of what your webapp needs, to process one request. > > The numer of concurrent users should be relatively irrelevant, if all you > mean by that is that some of these requests come from the same user, but > they are otherwise independent of one another. > > Note that I have a suspicion that what you describe as "requests" above > probably only count the requests to your webapp code, and do not count the > additional requests for stylesheets, images, etc.. which may be embedded in > any page that the user's browser eventually displays. > So unless you plan on serving those directly from the Apache httpd > front-end, you should take them into account too. > > > > ------------------------------**------------------------------**--------- > To unsubscribe, e-mail: > users-unsubscribe@tomcat.**apache.org<users-unsubscr...@tomcat.apache.org> > For additional commands, e-mail: users-h...@tomcat.apache.org > >
