View/Grade Assignment Fails (Page cannot be displayed)

View/Grade Assignment Fails (Page cannot be displayed)

by Noveck Gowandan -
Number of replies: 5

Moodle Version: Moodle 3.0.2+ (Build: 20160225)
Issue: In a large course (1400 students), lectures goes to assignment. Clicks title. 

Then clicks View/Grade all submissions.


IT takes 1-2 minutes then the page times out. (Page Cannot be Displayed)

If I click it as an administrator, the page loads.


Tech notes

Apache/2.2.15 

PHP 5.6.28 (cli)

mysqld  Ver 5.6.34 


Please help!


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In reply to Noveck Gowandan

Re: View/Grade Assignment Fails (Page cannot be displayed)

by Howard Miller -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers

Switch on Debugging recreate the fault. Check your web server's error log. What did you find?

You're probably exceeding some sort of limit. 

Average of ratings: -
In reply to Howard Miller

Re: View/Grade Assignment Fails (Page cannot be displayed)

by Noveck Gowandan -
Thanks, I don't know if this would help. I already have debugging enabled without piping to the actual page, goes straight to log.

Starts about here:


[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP Warning:  var_export does not handle circular references in /var/www/html/lib/classes/shutdown_manager.php on line 83, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP Stack trace:, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   1. {main}() /var/www/html/mod/assign/view.php:0, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   2. assign->view() /var/www/html/mod/assign/view.php:52, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   3. assign->download_submissions() /var/www/html/mod/assign/locallib.php:554, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   4. send_temp_file() /var/www/html/mod/assign/locallib.php:2728, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading
[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   5. readfile_accel() /var/www/html/lib/filelib.php:2049, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   6. readfile_allow_large() /var/www/html/lib/filelib.php:1969, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   7. core_shutdown_manager::shutdown_handler() /var/www/html/lib/classes/shutdown_manager.php:0, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   8. var_export() /var/www/html/lib/classes/shutdown_manager.php:83, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP Warning:  var_export does not handle circular references in /var/www/html/lib/classes/shutdown_manager.php on line 83, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP Stack trace:, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   1. {main}() /var/www/html/mod/assign/view.php:0, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   2. assign->view() /var/www/html/mod/assign/view.php:52, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   3. assign->download_submissions() /var/www/html/mod/assign/locallib.php:554, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   4. send_temp_file() /var/www/html/mod/assign/locallib.php:2728, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   5. readfile_accel() /var/www/html/lib/filelib.php:2049, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   6. readfile_allow_large() /var/www/html/lib/filelib.php:1969, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading
[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   7. core_shutdown_manager::shutdown_handler() /var/www/html/lib/classes/shutdown_manager.php:0, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   8. var_export() /var/www/html/lib/classes/shutdown_manager.php:83, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP Warning:  var_export does not handle circular references in /var/www/html/lib/classes/shutdown_manager.php on line 83, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP Stack trace:, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   1. {main}() /var/www/html/mod/assign/view.php:0, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   2. assign->view() /var/www/html/mod/assign/view.php:52, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   3. assign->download_submissions() /var/www/html/mod/assign/locallib.php:554, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   4. send_temp_file() /var/www/html/mod/assign/locallib.php:2728, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   5. readfile_accel() /var/www/html/lib/filelib.php:2049, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   6. readfile_allow_large() /var/www/html/lib/filelib.php:1969, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   7. core_shutdown_manager::shutdown_handler() /var/www/html/lib/classes/shutdown_manager.php:0, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] PHP   8. var_export() /var/www/html/lib/classes/shutdown_manager.php:83, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] Exception ignored in shutdown function array (\n  0 => \n  tool_log\\log\\manager::__set_state(array(\n     'readers' => \n    array (\n      'logstore_standard' => \n      logstore_standard\\log\\store::__set_state(array(\n         'logguests' => '0',\n         'manager' => NULL,\n         'component' => 'logstore_standard',\n         'store' => '',\n         'buffer' => \n        array (\n        ),\n         'buffersize' => '50',\n         'count' => 0,\n      )),\n    ),\n     'writers' => \n    array (\n      'logstore_standard' => \n      logstore_standard\\log\\store::__set_state(array(\n         'logguests' => '0',\n         'manager' => NULL,\n         'component' => 'logstore_standard',\n         'store' => '',\n         'buffer' => \n        array (\n        ),\n         'buffersize' => '50',\n         'count' => 0,\n      )),\n    ),\n     'stores' => \n    array (\n      'logstore_standard' => \n      logstore_standard\\log\\store::__set_state(array(\n         'logguests' => '0',\n         'manager' => NULL,\n         'component' => 'logstore_standard',\n         'store' => '',\n         'buffer' => \n        array (\n        ),\n         'buffersize' => '50',\n         'count' => 0,\n      )),\n    ),\n  )),\n  1 => 'dispose',\n):Error reading from database, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

[Thu Dec 01 10:33:26 2016] [error] [client 192.168.64.36] Default exception handler: Error reading from database Debug: MySQL server has gone away\nSELECT id, sid, state, userid, lastip, timecreated, timemodified FROM mdl_sessions WHERE sid = ?\n[array (\n  0 => 'v41uu2vnh0n0b4t3vd362rvdo3',\n)]\nError code: dmlreadexception\n* line 443 of /lib/dml/moodle_database.php: dml_read_exception thrown\n* line 1080 of /lib/dml/mysqli_native_moodle_database.php: call to moodle_database->query_end()\n* line 1480 of /lib/dml/moodle_database.php: call to mysqli_native_moodle_database->get_records_sql()\n* line 1452 of /lib/dml/moodle_database.php: call to moodle_database->get_record_sql()\n* line 1431 of /lib/dml/moodle_database.php: call to moodle_database->get_record_select()\n* line 278 of /lib/classes/session/manager.php: call to moodle_database->get_record()\n* line 79 of /lib/classes/session/manager.php: call to core\\session\\manager::initialise_user_session()\n* line 785 of /lib/setup.php: call to core\\session\\manager::start()\n* line 831 of /config.php: call to require_once()\n* line 25 of /mod/assign/view.php: call to require_once()\n, referer: http://mysitename.sanitized.com/mod/assign/view.php?id=22642&action=grading

Average of ratings: -
In reply to Noveck Gowandan

Re: View/Grade Assignment Fails (Page cannot be displayed)

by Noveck Gowandan -

I created another test teacher and this one is able to access the assignment submission list. Not quite sure why the two original teachers are seeing errors.

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In reply to Noveck Gowandan

Re: View/Grade Assignment Fails (Page cannot be displayed)

by Howard Miller -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers

Make sure your max_allowed_packet_size is big enough. See MySQL

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In reply to Howard Miller

Re: View/Grade Assignment Fails (Page cannot be displayed)

by Noveck Gowandan -
Thanks Howard.
The max_allowed_packet directive in mysql is currently 128M.
It's a pretty big dedicated DB server, with 64GB memory, so I don't believe that this is the issue.
Even when it is timing out, I don't see any spike in activity on the front end or back end servers.

I upped the Apache Timeout directive from 60 to 600.
What happens is that for these users, the page now times out after 10 minutes instead of 1. The odd thing is that it does not happen to everyone.

Is there some sort of per-user setting or view for assignments that may impact the loading of this page?



Average of ratings: -