Hi Lukas, Thanks for your response in length. As I mentioned earlier, I was not aware that the people from discourse forum and this email d-list group are same. I am 100% new to HAProxy.
Let me explain my current situation in-detail in this email thread, Kindly check if you or other people from the group can guide me. Our requirement to use HAProxy is NOT to load balance back-end (Weblogic 12c) servers, we have a singe backend instance (ex: PIA1), our server capacity is not high to handle the heavy traffic during peak load, the peak load occurs only 2 times in a year, that's a reason we are not scaling up our server resources as they will be idle majority of the time. we would like to use HAProxy to throttle http/tcp connections during the peak load, so that weblogic backed will not go to Out-Of-Memory state/PeopleSoft will not crash. To achieve http throttling,when setting maxconn to back end , HAProxy queue up further connections and releases once the active http connections become idle,however how weblogic works is, once the PeopleSoft URL is accessed and user is authenticated , cookie will be inserted to browser and cookie will be active by default 20 minutes, which mean even if user does not navigate and do anything inside the application, cookie session state will be retained in weblogic java heap. weblogic allocates small amount of memory in order to retain each active sessions (though memory allocation increase/decrease dynamically based on various business functionality i). as per current capacity , weblogic can retain only 100 session state , which means, I don't want to forward any further connections to weblogic until some of the sessions from 100 are released (by default the session will be released when user clicks explicitly on signout button or inactivity timeout reaches 20 minutes). according to my understanding, maxconn in back-end throttles connections and releases to back-end as and when tcp connection status changed to idle, but though connections are idle, logout/signout not occurred from PeopleSoft, so that still session state are maintained in weblogic and not released and cannot handle further connections. that's reason, I am setting the maxconn in front end and keeping HTTP alive option ON, so that I can throttle connections at front end itself. According to my POC, setting maxconn in front-end behaves differently than setting in back-end, when it is on front-end, it hold further connections in kernel , once the existing http connections are closed, it allows further connections inside, in this I dont see any performance issue for existing connections. for your information HAProxy and Weblogic are residing in a same single VM. please let me know if my above understanding is correct about maxconn. Is there any understanding gap ? is there any way to achieve my requirement differently? when decided to use maxconn in front-end, the connection queuing for few milli seconds and seconds are OK, but when connections are queued in minutes, would like to emit some meaningful message to user, that's a reason asked if there is any way to display custom message when connections are queued in Linux kernel. to answer Luaks question, weblogic does not logout user when tcp connection is closed. weblogic creates new connections as and when required. Best Wishes, Vel On Wed, Jun 28, 2017 at 9:47 AM, Lukas Tribus <lu...@gmx.net> wrote: > Hello Andrew, > > > Am 28.06.2017 um 02:06 schrieb Andrew Smalley: > > Lukas > > > > Why is this triple posting? Surely he asked questions in a nice way in > more than one location and deserves the right answer and not a flame down > here. > > > > It is about helping people after all I hope! > > Questions have been answered in a lengthy thread some 10 days ago: > http://discourse.haproxy.org/t/regarding-maxconn-parameter- > in-backend-for-connection-queueing/1320/9 > > No followup questions there. > > > Then a new thread today, no specific question that hasn't already > been answered in the previous thread, no followup responses (to my > request to clarify the question) either: > http://discourse.haproxy.org/t/custom-display-message-when- > setting-maxconn-in-front-end-listen-block/1382/2 > > > Then he moves the discussion to the mailing list, not mentioning the > conversations on discourse (which would prevented people - in this > case Jarno - from trying to explain the same thing all over again). > > > Its about helping people out, but that doesn't work in the long term > when we have people deliberately spread questions about the same topic > across different channels (mailing list, discourse). > > > > Lukas Tribus: > > Is there anything that has been answered 3 times already, or > > do you just like to annoy other people? > > This should have been: > Is there anything that has *not* been answered 3 times already? > > > > Velmurugan Dhakshnamoorthy: > > Apologize, my intent is not to annoy anyone > > [...] > > I am not aware this email group and discourse forum are same. > > The point is: please keep the discussion of a single topic/question > in a single thread (on the mailing list or discourse), unless you > don't get any responses. > > If something is unclear, you ought to ask for clarification, not > rephrase the question and ask somewhere else. > > > Lukas > >
