[b]Hibernate version: 2.1.6[/b]

Hello,

I've been using hibernate for abour 2 year of so, without many problems. The project I am on now requires us to retrieve up up to 15000 object per query. The app centers around querying this data, so we may need to raise the limt to 10s of thousands.

Anyway, it was taking at least 10-20 seconds per query of 7500. Long story short, I solved to problem by busting into the code to where the objects are created. If I am loading this master data class, I would short cut to a class i wrote to read from the result set and set the properties of my new class directly, avoiding the reflection.

With this modification I can load 80k object in about 20 seconds, or so the typical query of 10,000 or so is a manageable couple sec.

So I feel fairly confident that the CGLib reflection is where the time was spent.

Is there a good way to do this?

While I'm happy it works, and I encapsulated the code as much as possible, it still sucks, and is fairly brittle. If I upgrade to hib3 I have to redo. I can live with updating my "Custom Hydrator" since it is only for one of the classes.

Thanks for you help,
Nick

NO, it is not a cglib problem, but you can dissable "reflection optimizer" using system properties to test it.
This optimizer is faster than standard reflection, but the weight in query processing will be very small, if it takes 20 sec:

jdk 1.4.2_5 on windows

100000 objects

Standard reflection
544 ms. 0.00544 per iteration

Cglib
78 ms. 7.8E-4 per iteration

You can find this test in cglib CVS ( "net.sf.cglib.beans.TestBulkBean" )


Probably problem is a memory allocation for data structures to store result.

Thanks for the advice.

I'm sure this is a dumb question but,
I'm not sure how to increase my memory for the stored results. I've give the JVM a GB of memory to work with. Does hibernate or CGLIB some how constrain the amout of memory it works with?

Thank,
Nick

Hello nhruza1
I have the same problem. I'm executing a query which returns 17000 records and it takes about 30 seconds.
I would be very please if you could help me telling me in which part of the hibernate code I should make my modifications in order to make the Custom Hydrator

Thanks in advanced.

try to run this code in profiler and post statistics, it is possible to make it as fast as custom hydrator, we just need to reproduce it in simple test.

thank you for your help baliukas.
I'm sorry but I'm a new user with hibernate and I don't know how to do that (to run the code in profiler and post statictis)
what I have to do?

http://eclipsecolorer.sourceforge.net/i ... filer.html

there is good profiler in netbeans too.

That's good !

Thank you again.

I'm using eclipse so it's fit perfectly