graph_image.php fails to render a graph with 736 items.

[nullrouten]

I have a graph with 736 items being stacked. The graph image doesn't load... shows a broken image after 1 second. The headers on the image say HTTP 200, but length 0.

I can use graph debug mode to obtain the rrdtool command... and running said command manually produces a valid PNG... but graph_image.php fails silently. I've turned on php error logging... didn't show anything. cacti-0.8.8, centos (2.6.32-279.9.1.el6.centos.plus.x86_64), plenty of disk space and memory free, PHP 5.3.3, out of ideas over here... I have the rrdtool command that I copied right out of the webui (attached)... that runs fine, but not via the web ui.

If anyone has any ideas on debugging PHP, or just knows that I have too many items (and how to fix), that'd be great

[victorantunes]

To debug PHP, configure your php.ini to display errors on the page:

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display_errors = On

and to set the debugging level:

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error_reporting = E_ALL & E_STRICT

and restart Apache. Post the results after that.

[nullrouten]

Same... empty response, no error. (EDIT: I tested from the web UI and also the cli (as shown below)) If I simply delete some of the items in the graph (to bring the total number down) it works... but I haven't determined exactly what the limit is, or if its consistent graph to graph. It is affecting 3-4 of my graphs at this point (the 3-4 largest ones, as for item count).

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[user@netmon100 ~]$ grep -e ^error_reporting -e ^display_errors /etc/php.ini
error_reporting = E_ALL & E_STRICT
display_errors = On

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[user@netmon100 ~]$ sudo /etc/init.d/httpd restart
Stopping httpd:                                            [  OK  ]
Starting httpd:                                              [  OK  ]

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[user@netmon100 cacti]$ php-cgi graph_image.php action=view local_graph_id=8969 rra_id=5
X-Powered-By: PHP/5.3.3
Content-type: image/png

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[user@netmon100 cacti]$ curl -v "http://cacti.mydomain.net/graph_image.php?action=view&local_graph_id=8969&rra_id=5"
* About to connect() to cacti.mydomain.net port 80 (#0)
*   Trying 10.8.0.5... connected
* Connected to cacti.mydomain.net (10.8.0.5) port 80 (#0)
> GET /graph_image.php?action=view&local_graph_id=8969&rra_id=5 HTTP/1.1
> User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.13.1.0 zlib/1.2.3 libidn/1.18 libssh2/1.2.2
> Host: cacti.mydomain.net
> Accept: */*
>
< HTTP/1.1 200 OK
< Date: Tue, 21 May 2013 06:03:59 GMT
< Server: Apache/2.2.15 (CentOS)
< X-Powered-By: PHP/5.3.3
< Expires: Thu, 19 Nov 1981 08:52:00 GMT
< Last-Modified: Tue, 21 May 2013 06:03:59 GMT
< Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
< Pragma: no-cache
< P3P: CP="CAO PSA OUR"
< Set-Cookie: Cacti=t6lv6mktup9ijcgaeepolv2056; path=/
< Content-Length: 0
< Connection: close
< Content-Type: image/png
<
* Closing connection #0
[user@netmon100 cacti]$

[phalek]

Check you command line length limits:

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[server ]# getconf ARG_MAX
131072

On my Centos this is 131072 ( or 128kb )

your rrdtool command has a size of 133944 characters, so it wouldn't be able to run it on my Centos system. Will it do on yours ?

[nullrouten]

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[user@netmon100 ~]$ getconf ARG_MAX
2621440

The rrdtool command runs fine on a bash shell... just not via cacti. I too suspected some length limit of a variable, array, parameter, etc in PHP... but dont know what to check, and PHP isn't throwing any error when this happens. The memory limit for PHP is already at 256MB I think, and changing that to 512MB made no difference.

Thanks for the suggestion tho!

[nullrouten]

ping.

[flw521521]

i had to say,i got the same problem with you,my max item number of graph was 760,and i'm debuging it now and try to find out why
Have you fixed this problem?

[flw521521]

@gandalf
can you help us?
i think we are the most loyal users of cacti,we had made cacti in important use

[flw521521]

ping.

hi,can u tell me your progress of this problem?

[gajillion]

Any word on this? I have the exact same issue. I'm building aggregate graphs and the individual graphs work, but when I stack them together, the graphs with too many items fail silently.

[gajillion]

Any word on this? I have the exact same issue. I'm building aggregate graphs and the individual graphs work, but when I stack them together, the graphs with too many items fail silently.

Answered my own question. I straced the system call that HTTP was passing to rrdtool.

[/* 6 vars */]) = -1 E2BIG (Argument list too long)

This is an OS limitation and not a whole lot you can do about it.

[ivan777]

I had the same problem and I found what was the reason. Try to remove popen function from disabled_functions list in your php.ini file.
After I did that my graphs work like a charm. Here is more detailed instruction: http://druss.pp.ua/2014/11/solution-cac ... lem-fixed/ (I used it to solve this problem).

[karrakis]

Hello,

Sorry for forum diging... and Sorry for my English.

Is there some new information about the popen command line limit that is really lesser than the OS limit ? Did a bug was open for PHP ?

I have to make work a 1200 DataSources Aggregated Graph :/