[Qgis-developer] qgis-server will crash on a specific project

[Andrea Peri]

Hi,
thx for response.

meanwhile,
I notice that the max allowed layers is exactly 101.
This mean (knowing C/C++) an array of 100 elements.

Searching for this particular value,
i find in the file "mapserver/qgsmslayercache.cpp"
is defined
        mDefaultMaxLayers = 100;

if not defined the environment variable "MAX_CACHE_LAYERS"

char* maxLayerEnv = getenv( "MAX_CACHE_LAYERS" );
  if ( maxLayerEnv )


So a possible solution could be to set this environment variable.

I try and report.

Regards,

Andrea.


2014-06-22 12:07 GMT+02:00 Marco Hugentobler <marco.hugentobler at sourcepole.ch>:
> It is a problem with the layer cache. Will provide a fix for that soon.
>
> Regards,
> Marco
>
>
> On 22.06.2014 11:49, Andrea Peri wrote:
>>
>> Hi,
>>
>> I confirm.
>>
>> There is a layer limit in QGIS-Server
>>
>> I do a huge test removing one by one all the layers from my project.
>> And after the removing of every single layer I retest the working.
>>
>> Aftr a while of time. I reach the limit.
>>
>> And the project begin to run.
>>
>> I do other test to exclude that was the number of layer inside a single
>> group.
>> All the test give the response that seem to be the max number of
>> layers in a project.
>>
>> So the question is:
>>
>> QGIS desktop allow to put more layers rather than how many are
>> accepted from qgis-server.
>>
>> This not good for a WYSIWYG system.
>>
>> Ok, I will try to patch my server when found exactly where is the problem.
>>
>> Meanwhile,
>> Now the question is on what structure is this limit ?
>>
>> I don't guess it is simply a layer limit but perhaps a more specific
>> structure.
>>
>> Now I have a project that crash , and a project with a one less layer that
>> work.
>>
>>
>> Doing a DIFF beetween the two projects I see the possible structure
>> breakable are:
>>
>> layer-tree-canvas -> custom-order -> item
>> maplayer
>> Digitizing -> LayerSnappingList -> value   (type QStringList)
>> Digitizing -> LayerSnappingEnabledList -> value   (type QStringList)
>> Digitizing -> LayerSnapToList -> value   (type QStringList)
>> Digitizing -> LayerSnappingToleranceList -> value   (type QStringList)
>>
>> I check if in the code there is a limited array dimension for this
>> objects.
>>
>> Regards,
>>
>> Andrea.
>>
>>
>> 2014-06-22 7:29 GMT+02:00 Andrea Peri <aperi2007 at gmail.com>:
>>>
>>> Hi,
>>>
>>> I do some other tests.
>>>
>>> I take my project that give QG crash and split it in two compementary
>>> projects.
>>> Of course I do this using qgis desktop to avoid unvolontary errors.
>>>
>>> Testing both of them on QS there is no crash !
>>>
>>> So:
>>> The first plausible theory I can give is that Qgis-Server has a LIMIT
>>> to the number of Groups or Layers it can have in a project.
>>> A limit different (and less) than qgis desktop (osgeo4w version).
>>>
>>> Is this a plausible theory ?
>>>
>>> Thx,
>>>
>>> Andrea.
>>>
>>>
>>> 2014-06-21 22:04 GMT+02:00 Andrea Peri <aperi2007 at gmail.com>:
>>>>
>>>> Hi,
>>>> I have a qgis-server that will crash on a specific project.
>>>>
>>>> The qgis-server will run correctly with another project that seem
>>>> almost similar (both use the SVG symbols).
>>>>
>>>> The project that crash my QG  run correctly and smootly on a qgis
>>>> desktop (qgis-dev) on a windows system.
>>>> The project use SVG symbols, but also the other project I test on
>>>> QSused SVG symbol
>>>> so I suppose the SVG engine is ok.
>>>> Also I check t have set correctly the SVG paths.
>>>> Also I update to the very last (about 4 hours ago) master version.
>>>>
>>>> After all this check the qgis-server still crash.
>>>>
>>>> So I try to set the logfile, but the log is always empty.
>>>> This mean that the cgi qgis-server will crash almost immediatly.
>>>>
>>>> So I set an environment shell to run it manually and to test the cgi
>>>> with a gdb session.
>>>>
>>>> The results are this:
>>>>
>>>> ..................
>>>> [Thread debugging using libthread_db enabled]
>>>> Using host libthread_db library
>>>> "/lib/x86_64-linux-gnu/libthread_db.so.1".
>>>> Warning 1: Unable to find driver ECW to unload from GDAL_SKIP
>>>> environment variable.
>>>> Warning 1: Unable to find driver ECW to unload from GDAL_SKIP
>>>> environment variable.
>>>> Warning 1: Unable to find driver JP2ECW to unload from GDAL_SKIP
>>>> environment variable.
>>>> Warning 1: Unable to find driver ECW to unload from GDAL_SKIP
>>>> environment variable.
>>>> Warning 1: Unable to find driver JP2ECW to unload from GDAL_SKIP
>>>> environment variable.
>>>> [New Thread 0x7fffe307c700 (LWP 1844)]
>>>> [New Thread 0x7fffe27ea700 (LWP 1845)]
>>>>
>>>> Program received signal SIGSEGV, Segmentation fault.
>>>> 0x00007ffff4fc06da in qHash(QString const&) ()
>>>>     from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
>>>> (gdb)
>>>> ............................
>>>>
>>>> The version of libQtCore.so.4 I run on the linux is 4.8.2.
>>>>
>>>> Perhaps the 4.8.2 is too old for qgis-server ?
>>>> :/
>>>> But another project will run without any apparent problem.
>>>> ?
>>>>
>>>> Many thx for every hint.
>>>>
>>>> --
>>>> -----------------
>>>> Andrea Peri
>>>> . . . . . . . . .
>>>> qwerty àèìòù
>>>> -----------------
>>>
>>>
>>>
>>> --
>>> -----------------
>>> Andrea Peri
>>> . . . . . . . . .
>>> qwerty àèìòù
>>> -----------------
>>
>>
>>
>
>
> --
> Dr. Marco Hugentobler
> Sourcepole -  Linux & Open Source Solutions
> Weberstrasse 5, CH-8004 Zürich, Switzerland
> marco.hugentobler at sourcepole.ch http://www.sourcepole.ch
> Technical Advisor QGIS Project Steering Committee
>
> _______________________________________________
> Qgis-developer mailing list
> Qgis-developer at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-developer



-- 
-----------------
Andrea Peri
. . . . . . . . .
qwerty àèìòù
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