[Deploying Sakai] [Building Sakai] Strange database connection memory issue at U-M

[R.P. Aditya]

On 2009-09-17, Seth Theriault <slt at columbia.edu> wrote:
> Sean DeMonner wrote:
>
>> We've wondered that too, but haven't found anything that is 
>> running at those times. The jumps are also not consistently 
>> spaced so we haven't seen a pattern.
>
> I am thinking that there is some new JDBC-related code in 2.6 and 
> the database connections are not being closed properly (I guess 
> in this case, it would mean releasing the conns back to the 
> pool). I know that Michigan has the capacity to have a large sets 
> of results returned from any query.

We don't seem to have a connection "leak" as we're not running out of
pool connections and as far as I can tell from the logs, the
connections returned to the pool are not in some "wierd" state. It is
most likely that the per-connection (PGA session cache) cache in
Oracle is caching more than it used to (we increased the total amount
of PGA) and there is a particular request that is causing a large
resultset, as you suggest, being returned.

Thanks,
Adi