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From Ian Boston <...@tfd.co.uk>
Subject Re: LRUNodeIdCache maximum configuration ??
Date Sat, 27 Mar 2010 06:41:29 GMT
I want to ask some dumb questions, just in case.

How often do you do session.save() ?
Do you have any nodes with a large number of child nodes ? ( >2K)

If the answers to those are not often and yes, then they might be the cause of the problem.

Tuning the LRU caches will 
1. impact per session memory usage
2. may impact eviction processing on the cache (bigger caches take more time to do lru)
3. may make certain aspects faster as cache gets populated.

but, I don't think a cache that is too small will result in slow down compared to initial
operations, since unpopulated it will act in the same way as if it was small, but that does
depend on what you are doing.

One way to check if the cache is being inefficient is (assuming you are using a RDBMS based
Persistence Manager) see the proportion of select to update/insert traffic at the DB, and
see if that correlates to the slow down.


On 26 Mar 2010, at 21:23, JOSE FELIX HERNANDEZ BARRIO wrote:

> hi,
> I'm inserting data in batch process (near 200.000 items). At start time the
> process it's very quick, but after a few minutes the process performance go
> down. I've noticed that this happens when LRUNodeIdCache is full. Reviewing
> the source code for this class (LRUNodeIdCache) I've seen that maxSize is
> hardcoded to 10240.
> perhaps a code refactor to be able to configure this setting would be
> interesting.
> -- 
> Jose Hernandez
> 675599600
> Isthari
> http://www.isthari.com

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