Hrm, sounds like a hint :) We came up with this when we were DEEP in the weeds deploying our project and had trusted cisco's documentation that their router would function as expected. My boss was one of those guys who has been kicking around the area working longer contracts. You know the type, Phd in MIS or some such and about to retire. He called a friend who got this guy on the phone who told us about this solution. Banged it out in a day because Iplanet had the hooks for it. Took be a week to replicate in tomcat. Ugh. --Angus
> -----Original Message----- > From: Rick Roberts [mailto:[EMAIL PROTECTED] > Sent: Tuesday, August 05, 2003 10:52 AM > To: Tomcat Users List > Subject: Re: how to suppor 30000 concurrent users > > > I have always wondered how serious load balancing was done :) > Is this technique documented anywhere? > I would love to read up on it. > > Thanks > > Angus Mezick wrote: > > Ahh, the is the beauty of the cookie! All my servers respond to > > www.guidestar.org. I start a session, save that session id in the > > cookie, save the sessionid and data to the DB table that > all the servers > > share. The next request goes to a different server but it > can still see > > the id in the cookie. That id is used to get the session > data out of > > the table for use and then put the data back in. As long > as the DB can > > handle the load I can add servers. I am not worried about > the network > > handling the load because the only other way of doing this > that I know > > of is to use Filip Hank's In Memory Session Replication at > > http://www.filip.net/tomcat/tomcat-javagroups.html which uses IP > > multicast. I didn't want all my servers to get load every time one > > server got a hit. If the DB gets overloaded I can always split my > > servers into 2 groups and use apache session affinity to > split the work > > between them. Which leads to my next email :) Do the > worker names in > > worker2.properties and the jvmroute in server.xml have any relation? > > > > --Angus > > > > > >>-----Original Message----- > >>From: [EMAIL PROTECTED] > >>[mailto:[EMAIL PROTECTED] > >>Sent: Tuesday, August 05, 2003 10:25 AM > >>To: Tomcat Users List > >>Subject: RE: how to suppor 30000 concurrent users > >> > >> > >>Sorry for being thick but Im a bit confused as to when you > are doing > >>anything with the sessions? If I make a request to one > >>server, then go on > >>to another for the next request, how does server 2 get my > >>session from > >>server 1 without server 1 having had to persist the session > >>to disk every > >>time any change is made to it? > >>Pete > >> > >> > >> > >> > >> > >>"Angus Mezick" <[EMAIL PROTECTED]> > >>05/08/2003 15:11 > >>Please respond to "Tomcat Users List" > >> > >> To: "Tomcat Users List" <[EMAIL PROTECTED]> > >> cc: > >> Subject: RE: how to suppor 30000 concurrent users > >> > >> > >>Doesn't seem to have that much of an effect. I guess I > should profile > >>it though. I don't want to use session persistence because > >>then I would > >>need to use network session clustering. Session clustering is a > >>requirement for my app. I figure using a DB instead of > >>memory to store > >>my sessions is better than sending 5 network connections to > >>the other 5 > >>of the 6 web servers with the session data that will only > be valid to > >>ONE of those servers. Before tomcat we were using Iplanet > 4.1 and the > >>cisco load balance we have SAID it could handle session > >>affinity but it > >>didn't seem to be able to. So we went with a DB solution > >>which, to me, > >>seems to be the more optimal solution. The DB also means I > can have a > >>MUCH larger number of active sessions using my servers > because I don't > >>have to worry about the sessions using all my memory. I > just have to > >>worry about DB disk space but I had have 2 or 3 terabytes of > >>disk while > >>only have 2 GB of memory. Seems to be an easy trade. > >>--Angus > >> > >> > >>>-----Original Message----- > >>>From: [EMAIL PROTECTED] > >>>[mailto:[EMAIL PROTECTED] > >>>Sent: Tuesday, August 05, 2003 9:40 AM > >>>To: Tomcat Users List > >>>Subject: RE: how to suppor 30000 concurrent users > >>> > >>> > >>>Angus, > >>>doesnt using a shared jdbc based session manager slow the > >>>whole thing down > >>>a lot? Why dont you just use session persistence? > >>>Pete > >>> > >> > > -- > ******************************************* > * Rick Roberts * > * Advanced Information Technologies, Inc. * > ******************************************* > > > --------------------------------------------------------------------- > 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]
