perl - CGI problem

[Zhiliang Hu]

I wrote a perl program that retrieves data from MySQL database and do
some complex formating to export. In the program I used some scalar
variables to hold temporary intermediate data (~2MB).

While this program works fine on command line (takes more than 10
minutes). When I adept it as a CGI program, it works only when a small
data set is selected; When larger data set is selected, it fails
without error (return a blank page on web; no error to the Apache
server error log).

I wonder what could be the problem? I suspect the internal scalar
variable may exceed some sort of internal memory limit but I really
don't know -- therefore seem advice from experts on what should I look
into?

Thanks in advance!
Zhiliang

 

[A. Sinan Unur]

I wrote a perl program that retrieves data from MySQL database and do
some complex formating to export. In the program I used some scalar
variables to hold temporary intermediate data (~2MB).

While this program works fine on command line (takes more than 10
minutes). When I adept it as a CGI program, it works only when a small
data set is selected; When larger data set is selected, it fails
without error (return a blank page on web; no error to the Apache
server error log).

I wonder what could be the problem?

See http://www.stonehenge.com/merlyn/LinuxMag/col39.html

Sinan

--
A. Sinan Unur <[email protected]>
(remove .invalid and reverse each component for email address)

comp.lang.perl.misc guidelines on the WWW:
http://www.rehabitation.com/clpmisc/

 

[xhoster]

I wrote a perl program that retrieves data from MySQL database and do
some complex formating to export. In the program I used some scalar
variables to hold temporary intermediate data (~2MB).

While this program works fine on command line (takes more than 10
minutes). When I adept it as a CGI program, it works only when a small
data set is selected; When larger data set is selected, it fails
without error (return a blank page on web; no error to the Apache
server error log).

1st guess: The web browser is not willing to wait 10 minutes to get its
answer. It gives up with a time out.

Xho

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[Zhiliang Hu]

Thank you all for the hints. So if I send the job to background and
use a "transit page" to watch (by refresh) for the finishing of the
program, I should get by. I will try that out.

Best regards,

Zhiliang

 

[xhoster]

Thank you all for the hints. So if I send the job to background and
use a "transit page" to watch (by refresh) for the finishing of the
program, I should get by. I will try that out.

Another thing to try is to have the original script print a progress
character (like "+\n") every now and then, to keep the browser mesmerized.
It is quite a bit simpler than a refreshing transit page, and often gets
the job done.

Xho

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The costs of publication of this article were defrayed in part by the
payment of page charges. This article must therefore be hereby marked
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this fact.