00727: Unable to save large pages in latest pmwiki.

Summary: Unable to save large pages in latest pmwiki.
Created: 2006-04-26 19:00
Status: Closed - not reproducible
Category: Bug
Assigned:
Priority: 555
Version: 2.1.5
OS: Debian 3.1/apache-2.0.54-5/php4-common-4.3.10-16

Description: We experiencing problems with saving large pages. One of the developers in my school complained that after we migrated from 2.0.3x to 2.1.5 we cannot longer do it.

Example of such page is http://www.geosci.usyd.edu.au/pmwiki/pmwiki.php?n=GPlatesGMLDev.CategorisingFeatures This is a production page, but I think it is open for writing.

Is there anything I can do to help to trace this issue.


Version: 2.1.18 (latest)
OS: not sure

I am having the same problem with http://www.alientimes.org. The page that is causing the trouble is http://www.alientimes.org/pmwiki/pmwiki.php?n=Main.MasterIndex

This is a fairly serious problem for this site, as the Master Index feeds the home page and the breadcrumb trails.

Shaney


Odd. What happens when the page fails to save -- does it simply "time out" or is it saving an incomplete copy of the page?

Note that on pmwiki.org I was able to save a page containing two copies of the above Main.MasterIndex page (340KB!) -- see Test.LargePage.

Pm


Thank you for looking into this problem.

I add something to the page and then click on "save". The screen goes blank, still showing the address and ?action=edit in the address box. Nothing further happens. The screen stays blank.

In fact, this sort of thing has been happening for a while (perhaps one or two months -- I'm sorry, I can't remember what version I was using before and after this started happening), but in the past, the screen would go blank but if I then opened the page in another tab, the changes would have been saved. In the current situation, the screen goes blank and the changes are not accepted. This new result has been happening since yesterday. (After I noticed this problem yesterday, I upgraded to 2.1.18, but the problem didn't change.)

I thought that perhaps something in the content that I am trying to add was causing the problem, but then I was able to save the content properly on a different page. Then, I wondered if the page was just too long, but that doesn't seem to be the case because I can't even DELETE stuff from the page now.

A few times when I was trying out different things to try to get the changes accepted I did get a server error. I haven't been able to re-create this server error yet today, but it may have been a 500 internal server error. I will fiddle some more today to see if I can get the same error. (Sorry for the imprecision!)

Shaney


Okay, I was able to get the error.

Here's what I did. I decided to try to delete everything (ctrl-x), save the page, open it again, paste the contents (ctrl-v), and save again. This worked, even with the extra few lines I wanted to add. Then, I wanted to go in and touch up a couple of spots where line breaks had snuck in.

This resulted in the following error.

   Title: 500 Internal Server Error

   Internal Server Error

   The server encountered an internal error or misconfiguration and 
   was unable to complete your request.

   Please contact the server administrator, advancedsupport[at]ensim.com 
   and inform them of the time the error occurred, and anything you might 
   have done that may have caused the error.

   More information about this error may be available in the server error log.

   Apache/2.0.51 (Fedora) Server at www.alientimes.org Port 80

Shaney


Tried to do the same on Test/LargePage. Was able to add the extra lines (although it took a looooooooong time to save). And then I was also able to make the corrections to the page breaks.

Does this mean that it is a problem with my server?

Shaney


Coincidentally, I ran into problems today merely viewing a large page (700 kB) that had been automatically generated by Cookbook.ActionLog. My attempt to view the file did not yield any result, but I promptly got a call from another user who experienced a type 500 error, I believe as a side effect of the server being busy with my request.

One might want to check the max execution time allowed in the PHP settings as this tends to interfere with very long execution times (in my case, with long downlads through PmWiki - that is, with direct downloads disabled) but my impression is that with typical server hardware, there is a certain limit to what PmWiki can handle size-wise. (I'm just a user, though, not a programmer.) --Henning August 31, 2006, at 09:25 AM


I just tried to add something to the long page from a different computer (on a different day). This time, the server error came up immediately.

Shaney


Okay, even stranger results. I now can't add or delete anything from the Main.MasterIndex page without getting an immediate server error, but I copied everything over to Main.MasterIndex2 and I can add and delete things normally on that page (the blank screen thing still happens, but the changes are saved).

I have even linked the home page and the wiki trail to the new MasterIndex2 page and can still edit the new index page.

How could it be that one single page causes all kinds of errors, but an identical page is basically fine? It seems not to have to do with the length of the page, necessarily, but I don't know what else it could be, because it hasn't happened with any other page that I have found.

Shaney


Last night, I tried to fix the problem by manipulating the actual files on the server, to no avail. I copied the Main.MasterIndex2 file over top of the Main.MasterIndex file, but I was still not able to make changes to Main.MasterIndex. Main.MasterIndex2 still worked fine, except for the blank screen problem (the screen goes blank when I press save, but the changes are saved when I look at the page in another tab). It's like the server took a particular dislike to the original Main.MasterIndex page.

However, this morning, I tried to edit Main.MasterIndex and... succeeded! I will try to link the home page and the wiki trail back to Main.MasterIndex and see what happens.

I really can't explain this bug. It seems to be rather random, and perhaps has more to do with the server than with the pmwiki software.

Shaney September 01, 2006, at 06:32 PM