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From Marko Ciric <ciric.ma...@gmail.com>
Subject Re: Connection Pooling
Date Thu, 21 Jul 2011 12:40:25 GMT
Actually, as GenericDataModel class works very well as a super class of your
desired data model. This way everything is cached into memory and boosts
performance a lot. The reloading is actually easy to be implemented with the
refresh mechanism (Taste objects implement Refreshable interface). You can
also try RefreshHelper.

On 13 July 2011 20:58, Sean Owen <srowen@gmail.com> wrote:

> I was mixing this up with another class. It doesn't reload itself. You can
> call refresh() to do so.
>
> On Wed, Jul 13, 2011 at 7:34 PM, Salil Apte <salil@offlinelabs.com> wrote:
>
> > Where can the interval be configured? BTW, ReloadFromJDBCDataModel
> > works like a dream so far :)
> >
> > On Wed, Jul 13, 2011 at 10:58 AM, Sean Owen <srowen@gmail.com> wrote:
> > > Yes it reloads after a configurable interval, or on demand.
> > >
> > > Clearing the cache for a user ID only means that user's data is
> > recomputed.
> > > It's not bad to call this frequently per se... I suppose you want to
> let
> > it
> > > cache as much and for as long as is valid and acceptable to your app.
> > >
> > > Your bottleneck is no longer reading from the DB if you're having it
> load
> > > into memory.
> > >
> > > On Wed, Jul 13, 2011 at 6:19 PM, Salil Apte <salil@offlinelabs.com>
> > wrote:
> > >
> > >> Awesome, I will give ReloadFromJDBCDataModel a try. How does this
> > >> particular data model update itself on database changes? Does it just
> > >> happen periodically and if so, can this rate be change easily?
> > >>
> > >> Lastly, will calling clear(userId) on a recommender frequently be bad
> > >> for performance? I'm assuming with such small data amounts that the
> > >> actual recommendation algorithm is quite speedy and that the DB is
> > >> really the big bottleneck?
> > >>
> > >> On Wed, Jul 13, 2011 at 2:11 AM, Sean Owen <srowen@gmail.com> wrote:
> > >> > That's all correct, it reads a lot. But you can avoid a lot of it
by
> > >> using
> > >> > caching wrappers.
> > >> > You also don't need to dump to a file. Use ReloadFromJDBCDataModel.
> > >> >
> > >> > On Wed, Jul 13, 2011 at 9:57 AM, Vitali Mogilevsky
> > >> > <vitali@playedonline.com>wrote:
> > >> >
> > >> >> Hey,
> > >> >> I got the same problem, of slowness while using MYSQL data model,
> > after
> > >> a
> > >> >> small research and looking into mysql's query log, revealed that
> user
> > -
> > >> >> user
> > >> >> recommendation just floods the database with thousands and
> thousands
> > of
> > >> >> requests.
> > >> >> and thats on small database.
> > >> >> for now Im dumbping the database into file, and using filedata
> model
> > >> which
> > >> >> works much faster
> > >> >>
> > >> >>
> > >> >
> > >>
> > >
> >
>



-- 
--
Marko Ćirić
ciric.marko@gmail.com

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