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From Fabio <pruef...@me.com>
Subject Persisting ~10**4 entities takes 100-1200 sec
Date Sun, 22 Feb 2009 08:44:35 GMT

I'm using Derby (latest version) in embedded mode in a Swing  
application. As JPA Provider, I'm using TopLink Essentials (2.1 Build  

Basically, the app grabs some data from the web and stores it in the  
embedded database. However, the storing process takes quite a while.  
Here's a code snippet:

		ArrayList<Load> load_data = grabHourlyLoadForMonthAndYear(month,  
	        if (load_data.size() > 0) {
	            	System.out.println(load_data.size()+" objects");
		        for (Load l : load_data)
		        long start = System.currentTimeMillis();
		        System.out.println("time: "+ ((System.currentTimeMillis()- 
start)/1000) + " sec");
grabHourlyLoadForMonthAndYear() grabs the data from the web. "em" is  
the EntityManager.
The entity "Load" has 5 fields (id, country, year, hourInYear, load)

A typical output looks like this:
	17856 objects
	time: 102 sec
	16128 objects
	time: 551 sec
	17856 objects
	time: 1200 sec

As you can see, the time increases drastically while the number of  
objects doesn't. From a usability standpoint, that's way too much time  
spent on waiting.

Has anyone seen similar slow downs while using Derby together with  
TopLink Essentials in a desktop application?

Best Regards

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