0 Replies Latest reply: Feb 1, 2012 2:27 AM by Frédéric Villemin RSS

    Lost connection when too many users

    Frédéric Villemin

      Hi,

       

      i am doing load tests on my QV10R4 Server and i have quite strange behaviour.

       

      I am using a 30MB .qvw. The server is a 8xcpu, 12gb ram, using QV Web Server and Ajax mode

       

      I am launching a test program to simulate ~10 users to navigate in this document. And while it is running, i'm trying to access the same document.

      Almost everytime it may work a bit but i begin having "Lost Connection to server" errors.

       

      It doesn't seem to be a timeout as it happens as soon as i click a list box : i click a selection, i wait 1 second and it tries to reconnect (and manages to reconnect)

       

      When i look at the server's CPU and RAM, qvs.exe doesn't use more than 50% CPU with ~1GB RAM, qvwebserver.exe uses something like 50MB RAM and never goes more than 10% CPU .. and there is nothing else happening on the server...

       

      It seems that with other .qvw, even bigger, it works better..

       

      I wouldn't care having people wait more when there are many users connected but not being disconnected when the Server doesn't seem to work at 100%

      What's your opinion about that ? what can be the problem ? 

       

      QV Web Server ? specific timeout or limited number of connections ?

      Timeout ? a specific timeout for each Ajax call ? (very low ?)

      Network ? too many connections at the same time in the network ?

      QVS ? too many requests even if CPU <50% ?

      Document ?  use of complicated reports ? (many text boxes with 2 color backgrounds but almost no set analysis report)

       

      (tests on QV11 report almost the same result, at least the same Lost Connection error when many users)

       

      EDITION : just to be more precise, this behaviour seems to happen especially when each user is using more than 4 connections at the same time or when using Chrome (which probably sends multiple connections at the same time, at least, more than IE). If i use only 2 connections per user (10 users) and using a IE at the same time, it doesn't occur. Is it a big number of simul requests from the same user which annoys the Webserver ?

       

      Message was edited by: Frédéric Villemin