[Building Sakai] Stats Tool

[Matthew Buckett]

On Thu, May 9, 2013 at 10:09 AM, Matthew Buckett
<matthew.buckett at it.ox.ac.uk> wrote:
> On Thu, May 9, 2013 at 8:12 AM, Nguni Phakela <nguni52 at gmail.com> wrote:
>>
>> Thank you for the reply. So that means the stats will still be accurate even
>> with the daily cleaning of the SAKAI_SESSION and SAKAI_EVENTS table?
>
> It is possible to configure sitestats to process events in batches
> overnight (using the quartz scheduler) in which case you need to be
> careful about when you do you cleaning of the session and event
> tables. Are you currently using the live processing of events or the
> batch processing?

Just to be clear sitestats by default spawns a thread on each tomcat
instance which watches for events, stores them in memory and then
every 4 seconds updates any records in the SST_* tables with the new
events. If you are experiencing high load you can slow down the rate
at which it updates it's tables, but it's a balancing act. If you ask
sitestats to only update it's records event 12 hours then it has to
hold details of all the event changes in memory which may well cause
problems.

This is why it also supports using a quartz job which rather than
watching for events as they happen and keeping them in memory it loads
events out of the database, process them and updates the SST_* tables
in batches.

Another thing to think about is moving the SST_* tables to a separate
database server so it's doesn't impact on the performance of the rest
of the system. Sitestats supports using a different database
connection to the rest of Sakai.

-- 
  Matthew Buckett, VLE Developer, IT Services, University of Oxford