Michael. I am a bit new to deployment and related stuff, so can you tell me how to run more than one tomcat on a single machine. Is the process is same as having load balancing tomcat clusters on different machines. or Please direct me towards any documentation on this. I will get the info from there.
regards Srikanth On 7/22/05, Michael Kleinhenz <[EMAIL PROTECTED]> wrote: > Peddireddy, > > > your mail is very informative. > > we have a very similar set up (4 Xeon processors 3.5 GB Ram and > > WIn2003 Standard edition) and hardpart is that we cant change this > > setup and switch to Linux. > > same problem over here. The computing centre of our client can't provide > Linux servers. I'm struggling with this problem for 3 weeks now. > > > I heard about clustering on diferent boxes. Is the process of running > > multiple tomcats on a single machine will be same?? > > My experience was that with a single Tomcat on a large machine, you'll > never use that box fully. Besides that you can't get the Sun JVM to > accept a large amount of threads while giving them enough memory, Tomcat > seems to have performance problems with 3000+ threads busy at the same > time. The BEA JVM (JRockit) performs better in terms of memory and > threads but is slower than the Sun JVM. If you have rather complex > database operations performed by your webapp, this will get you into > trouble, because if there is a single bottleneck in the whole system, > the requests will pile up in the server, it hits its thread limit, and > ceases operation. > > So, I have made good experiences with 4 Tomcats on a 2xXeon with 4GB. > The server's load is somewhere between 70% and 100% while running with > high load and can handle more concurrent requests than a single Tomcat. > > > You talked about some "workarounds using esoteric registry keys", can > > you eloborate on this or tell me where I can get details about it and > > the details about limitations placed by windows2003 on a single > > process in terms of number of threads, memory etc. > > We use 2003 Standard Edition and get the following limitations: > > . Windows only provides 2GB memory to all applications running, > regardless of how much memory you have. All other memory is used for > Windows itself. With a registry key, you can extend this to 3GB. I > don't have the key handy, but it can be found in MSDN. > > . The somewhat larger problem is the crappy TCP stack on Windows. A > single Tomcat easily handles 1000 concurrent connections, but if I start > 4 Tomcats, I get a WSAENOBUFS error ("An operation on a socket could not > be performed because the system lacked sufficient buffer space or > because a queue was full") at about 3300 concurrent connections. > Because each Tomcat runs with his own instance of the JVM, I suppose > the problem is Windows, the network or anything else that is used by all > Tomcats at the same time. Even worse, after such a crash, there is a > 10% chance, the Tomcats not resuming normal operation but crashes > completely. > > . Windows has a default limit of 5000 ephemeral ports that can be used > fo outgoing connections. This can be changed with the MaxUserPorts > registry key. Also, the TcpTimedWaitDelay key is relevant for network > performance. Both are described here: > > > http://msdn.microsoft.com/library/en-us/randz/protocol/tcp_time-wait_delay.asp > > I'm now really irritated by this problem. I need a capacity of about > 15000 concurrent connections for my project. I also have 3 2xXeon > servers here, but windows (or anything else) doesn't allow more than > ~8000 connections until it dies. > > -- Michael > > -- > Dipl.-Technoinform. Michael Kleinhenz > tarent GmbH . Bahnhofstr. 13 . 53123 Bonn > fon +49 (228) / 52 67 5-0 . fax +49 (228) / 52 67 5-25 > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]