4 Replies Latest reply: Mar 19, 2013 8:48 AM by CraigB RSS

    slow response from user input

    GregorM
      Hi.

      I have a very strange problem with some of my clients. Sometimes they experience a huge delay between key pressed on keyboard and actual character printed on monitor. So there is a simple text item involved and when the user starts typing the delay could be two or even three seconds between user input (each character) and actual forms displaying it.

      First I suspected network contention but I am not quite sure if there is any network traffic (client browser -> application server) involved while user is typing text into text item. Next I tried to monitor clients machine processes (like anti virus program) but no luck. I have also tried various JRE versions but again no luck.

      I am using 11.1.2.1 version of forms with Mozilla and JRE 1.6.35 on client side.

      Does anybody have/had similar experience? Any suggestion in helping resolving the issue appreciated.

      Also I am really curious what is happening (is there any network traffic involved) while user is typing text into text item where there is no trigger on that item except when_validate_item.

      Best regards.
        • 1. Re: slow response from user input
          CraigB
          Also I am really curious what is happening (is there any network traffic involved) while user is typing text into text item where there is no trigger on that item except when_validate_item.
          Unless you have implemented a Java Bean on the item to monitor the keystrokes in the field, no events are trigger by the act of typing characters in a field. The act of typing characters in a field occurs completly on the client - no network traffic at this point. Only when a field event occurs (navigation away from the item) will an event occur that would cause network communication between the client and the appilcation server.
          Sometimes they experience a huge delay between key pressed on keyboard and actual character printed on monitor.
          I encountered something similar to this with a user once who complained about how slow the application ran on their computer. The slowness was intermitant and there was no apparent pattern. Like you, I looked at JRE and other things. Finally, told the user to call me when the slowness occured so I could come look at the computer while it was occuring. Turns out, the user had at least 30+ applications running at the same time. The workstation was running Windows XP with 2gb Ram. Looking at their system resources, there was no memory available and the pc was memory thrashing really bad. I had the user close all but the absolute necessary programs and our Forms application started responding quickly again. After a little user education - miraculously, the slowness problem went away. :)

          Craig...
          • 2. Re: slow response from user input
            GregorM
            Hi.

            Craig thank you for your explanation. As you described, I also ran to the customer when things went slow. But at the time I got there application started to work smoothly - sounds familiar :-) However I also installed the process monitor (sysinternals) tool on client machine to be able to capture offensive processes that might brought application response down. Again no luck. Today after I posted the question I have made a little experiment.

            I have create a 3 text item form with no triggers, java beans ... what so ever. I have deployed that form to the application server at work. As I got home (so the network bandwidth would be limited to 8Mbit/sec) I have run that form and there was no contention or delay on input to text item. Next thing I have started utorrent software and started to download a couple of files to fill the network bandwidth. Guess what I have got the delay when writing text to text fields. So my first impression is there is something going on while typing. Although I must say I had exactly the same understanding as you that typing occurs solely on the client side. Tomorrow (as it is getting late) I will try to do some tcpdump on the client to see what exactly is going on.

            Anyway thank you for sharing your experience.

            Best regards.
            • 3. Re: slow response from user input
              GregorM
              Hi.

              Craig you were right there is no network traffic involved when the data is typed into text item. It seems there was only circumstances yesterday that lead me to doubt in your explanation. Could I ask you two more questions? Did you narrowed down the problem you had? Was it cpu consumption, memory filled up,...? What was the browser your users were using?

              Thanks.

              Best regards.
              • 4. Re: slow response from user input
                CraigB
                Was it cpu consumption,...
                This was a contributing issue, but CPU usage was only about 25-30%.
                ...memory filled up,...?
                This was the biggest issue. All available RAM was used and the Virtual Memory was used up as well. Therefore, Windows was having to read and write constantly to the disk in order to do anything. Consequently, there was massive amounts of disk-trashing and I/O bottlenecking.
                What was the browser your users were using?
                At the time, we were using Internet Explorer 6 and Firefox 3.6.

                Craig...