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Moodle cache clearance

We have hosted Moodle in our University campus catering to 1200 users. All the quizzes and some exams are also conducted in Moodle in our campus.

Last week we accommodated nearly 180 students for taking a quiz which contains images, sounds, and text information. After sometime, the Server hangs to satisfy the needs of the user. So we end up in a situation where we need to stop the quiz and let the students go.

And after searching the net and the system Event Viewer, there was a mistake in two moodle tables. One is "mdl_message" and another is "mdl_cache_text". Event viewer of windows tells that the above two table have crashed and has to be repaired.

I issued a SQL Query "REPAIR TABLE mdl_message" and "REPAIR TABLE mdl_cache_text"

but still then the issues are not cleared. so i empty the table "mdl_cache_text" and it was working fine then on.

Moodle uses a table called "mdl_cache_text" which cache the texts that are used in assignments, quizzes, messages, etc. The above table updates automatically over time. So if you are running your Moodle server for long time, obviously you may have a feel that the system is so slow.
here is the way to make your Moodle to act fast.
1. Go to your phpmyadmin or the database which you are running Moodle (In my case it is http://localhost/phpmyadmin)

2. click the database "Moodle" or (whatever you have given) and select the table "mdl_cache_text"

3.  "REPAIR TABLE mdl_cache_text"

4. Just Empty the table by selecting the Empty tab in Phpmyadmin or else issue the SQL Query "TRUNCATE TABLE mdl_cache_text" (without quotes)

5. Clear all the event logs of your operating system. Now access Moodle, it will be quite fast.

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