The site crashes when have high volume connections. Normally it is fine. 
In the orientation day,  there were about 40 to 60 (?) ipads in a room, there are 10(?) rooms, some loose users (10?) in the hall way. So I would image the concurrent user is about 400 to 600. 
Vufind server is installed in Virtual Machine with 2 CPU 4 GB Memory. Can someone help to answer following questions? 

Should we set the max concurrent user to 800 to 1000? If there are only 100 concurrent users regularly, is this big number bad?   This setting is in where? 
I was told MaxRequestWorkers is set to 150, should it set higher?  in what file?  I can not find it.
What're the other settings that need to be adjusted to work with high volume concurrent setting? 
How much memory needs to be added?
Does CPU need to be increased  too? 
Does PHP memory allocation need to be increased too? 

Any suggestion and more detail instruction is highly appreciated.

Fang


On Wed, Jul 2, 2014 at 12:43 PM, Fang Peng <fang.peng@stonybrook.edu> wrote:
I got a report and said " the web site was crashed" and after a while it come back.  I checked log file and found the error messages as following (two kind errors). Anyone know what it means ? 


[Mon Jun 30 15:43:12.182304 2014] [:error] [pid 21079] [client 129.49.202.88:61369] PHP Catchable fatal error:  Argument 1 passed to Zend\\Db\\RowGateway\\AbstractRowGateway::populate() must be of the type array, boolean given, called in /usr/local/vufind2/vendor/zendframework/zendframework/library/Zend/Db/RowGateway/AbstractRowGateway.php on line 182 and defined in /usr/local/vufind2/vendor/zendframework/zendframework/library/Zend/Db/RowGateway/AbstractRowGateway.php on line 97, referer: http://129.49.23.240/vufind/Search/Results?type=AllFields



[Tue Jul 01 14:22:21.901010 2014] [:error] [pid 35500] [client 38.105.236.163:31032] PHP Fatal error:  Class 'ComposerAutoloaderInit1374cb774f67d4088a0cd7dca4331c3f' not found in /usr/local/vufind2/vendor/autoload.php on line 7, referer: http://129.49.23.240/vufind/Search/Results?type=AllFields&filter[]=author2%3A%221148PHY133A%22&submit=Find
[Tue Jul 01 14:22:21.901175 2014] [:error] [pid 35500] [client 38.105.236.163:31032] PHP Notice:  Constant ORIGINAL_WORKING_DIRECTORY already defined in /usr/local/vufind2/public/index.php on line 28, referer: http://129.49.23.240/vufind/Search/Results?type=AllFields&filter[]=author2%3A%221148PHY133A%22&submit=Find
[Tue Jul 01 14:22:21.901208 2014] [:error] [pid 35500] [client 38.105.236.163:31032] PHP Fatal error:  Class 'ComposerAutoloaderInit1374cb774f67d4088a0cd7dca4331c3f' not found in /usr/local/vufind2/vendor/autoload.php on line 7, referer: http://129.49.23.240/vufind/Search/Results?type=AllFields&filter[]=author2%3A%221148PHY133A%22&submit=Find
[Tue Jul 01 14:22:27.238215 2014] [:error] [pid 34678] [client 38.105.236.163:32461] PHP Fatal error:  Class 'ComposerAutoloaderInit1374cb774f67d4088a0cd7dca4331c3f' not found in /usr/local/vufind2/vendor/autoload.php on line 7, referer: http://129.49.23.240/vufind/Search/Results?type=AllFields&filter%5B%5D=genre_facet%3A%22SNW+Study+the+Natural+World%22&filter%5B%5D=ctrlnum%3A%22Fall+2014%22&filter%5B%5D=collection%3A%22WEST+CAMPUS%22&page=7
[Tue Jul 01 14:22:33.415932 2014] [:error] [pid 35429] [client 38.105.236.163:13469] PHP Notice:  Constant ORIGINAL_WORKING_DIRECTORY already defined in /usr/local/vufind2/public/index.php on line 28, referer: http://129.49.23.240/vufind/Search/Results?type=AllFields&filter%5B%5D=genre_facet%3A%22SNW+Study+the+Natural+World%22&filter%5B%5D=ctrlnum%3A%22Fall+2014%22&filter%5B%5D=collection%3A%22WEST+CAMPUS%22&page=7
[Tue Jul 01 14:22:33.681804 2014] [core:notice] [pid 1613] AH00051: child pid 35429 exit signal Segmentation fault (11), possible coredump in /etc/apache2




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Fang Peng
Information Systems Access Control Manager /DoIT
Stony Brook University 
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