Re: Oracle Forms WAN Performance

Keith Fulton wrote:

> I have a application which is implemented as around 180 fmx files in 16bit
> Forms 4.5. Each fmx is coded to contain 1 window (with multiple canvases,
> etc.). Window-to-window navigation is accomplished by calling and executing
> the new fmx in each case. This works pretty well from a version control and
> maintenance standpoint, but I believe it is causing us problems with
> performance. Each fmx is taking like 10 - 20 seconds to open even on the LAN,
> and the files are only 150-300K apiece, so it isn't the file server. Over the
> WAN, the fmx's are still on a LAN file server, so it is not an issue there
> either.
>
> The issue *seems* to be all the initialization that Forms does when it opens a
> new fmx file--it issues something like 30-40 queries for information such as
> the date format, the currency, the language, etc.--items which are never used
> by any of the forms.
>
> Surely all Forms applications aren't this slow. What are we missing here? Is
> this initialization code in a package we can remove? Is there some
> command-line parameter we missed to turn off all this stuff or what?
>
> Thanks for your help in advance,
> Keith Fulton

  I have recently finished a project which used F45 over a WAN. We had none of the problems that you describe. Remember that over a WAN both latency and bandwidth are important. Latency is a measure of the length of the path between the client and the server. A single packet takes about 6 ms to travel a kilometer over a 64Kbs ISDN WAN. So if your server is in SF and your clients are in the UK, then you may experiance problems.

In addition, you should be careful to base all blocks in your forms on queries so any denormalisation is carried out on the server. I.e, your forms should not have any POST-QUERY triggers to populate descriptors for foreign-key values.

Part of my duties on this project was to provide technical assurance of the viablity of our design over a WAN. I carry out this duty I used a tool called Optimal Application Expert. This tool can measure the network characteristics of an application using TCP/IP on for instance a LAN. It can then predict the application performance if it were forced to work over a different type of network, for instance a WAN. I used this tool with great sucess and found its predictions extremely accurate. I would recommend that you use this tool in your development process so that forms which perform badly over a WAN can be identified whilst they are still on a LAN.

Best Wishes. Received on Sat Jun 06 1998 - 05:18:20 CDT