Hello, (this may be related to the "Performance testing?"-thread)

IMHO there is a problem with the statistics for a survey. I installed and activaed jpgraph to enable graphical statistics. The site is hostet at 1&1, a german web provider. 1&1 (like many other web hosting providers) has a hard limit of 10 seconds per process (this is NOT configurable with ini_set() or sth like this), processes running longer than 10 seconds are killed.

The problem is: If I generate the statistics for a moderately sized survey (about 30 answers for about 15 questions) I get a progess bar. This progress bar just stopps after about 20 seconds (because the process is killed). Without jpgraph, everything works fine. If I select single answers, the generation time is also drasically reduced and everything works (with graph).

I'm using LimeSurvey 1.52, so not the newest version 1.7. And I don't know if something changed in the new version, regarding the generation speed of the images. So my questions are:

1. Does the newest version have any speed improvements regarding graph generation?

2. Is there is something else *I* can do to speed up the process?

3. Would it be possible (for *you* developers) to implement a "group by group" or "question by question" statistic to avoid long process runtimes? (This is a kind of low-priority feature request).

4. Whats causing the long runtimes? Is the generation of the graphs really that time consuming? Or is this caused by a "bad" implementation that need attention?

Regards,
Simon Fuhrmann

Hi, yes there have been some speed improvements for exporting large survey, but not for JPGraph.

But there is a new option to do a graphical output with jpgraph or not!

I really suggest to update to the latest version - 1.70+

Simon wrote:
4. Whats causing the long runtimes? Is the generation of the graphs really that time consuming? Or is this caused by a "bad" implementation that need attention?
The generation of the graphs is really time-consuming, especially for greater amount of data. The influence to speed up the graph creation is quite limited because jpgraph only gets one/two arrays from limesurvey to create the graphic out of it.

Please test our newest 1.70 release and report if you notice any kind of speed up.

Hello! Sorry for the delay.

I updated to version 1.70 and indeed, the generation of the graphics works. I'm not sure why the generation is that much faster now. JPGraph is still used as rendering engine. Anti-aliasing does not work, it takes too long.

Regards,
Simon

Simon wrote:
Hello! Sorry for the delay.

I updated to version 1.70 and indeed, the generation of the graphics works. I'm not sure why the generation is that much faster now. JPGraph is still used as rendering engine. Anti-aliasing does not work, it takes too long.

Regards,
Simon

Thanks for your feedback. Anti-aliasing is indeed an enormous performance killer. It's just like playing modern ego shooters: If you want to run fast you have to disable anti-aliasing, too.

I think I'm having the same problem. When I try to view the graphical summary, I get the following error:


Warning: require_once(/mnt/Target01/337283/342477/www.thehoya.com/web/content/survey/src/jpgraph.php) [function.require-once]: failed to open stream: No such file or directory in /mnt/Target01/337283/342477/www.thehoya.com/web/content/survey/admin/statistics.php on line 27

Fatal error: require_once() [function.require]: Failed opening required '/mnt/Target01/337283/342477/www.thehoya.com/web/content/survey/src/jpgraph.php' (include_path='.:/usr/share/php:/usr/share/pear' in /mnt/Target01/337283/342477/www.thehoya.com/web/content/survey/admin/statistics.php on line 27


Any ideas? If I update to 1.7 will I lose the survey data?

An update from 1.53 to 1.70 is possible without any problems. Of yourse you won't loose data. Please read the manual on how to upgrade.

Nevertheless your problem seemst to be connected to the fact that you havent't configured jpgraph correctly. Please check the follow sections of the manual:
- installation
- statistics

Please check the path settings for jpgraph in config.php.