Java Collections vs in-memory database performance

Question

I am not sure whether to use Java Collections or some in-memory DB (H2 or HSQLDB - they are probably the fastest). I need a good performance results - there will be hundreds of objects/rows, no JOIN or more complex queries would be performed.

I am really considering in-memory DB, because of limited size of java heap - the objects that I am working with may be quite large and also there will be a lot of them (hundreds as I mentioned)

do you think it is a good idea to use in-memory database for a large amount of data?

in modern terms, hundreds of objects aren't much. When you say that the objects will be big -- how big? — Sheriff
– Sheriff, Commented Feb 14, 2012 at 18:56
Hundreds of objects is laughable, even if each object has a hundred fields. Besides, the memory has got to come from somewhere, and a DB will likely add some overhead. — user395760
– user395760, Commented Feb 14, 2012 at 18:56
Well, hundreds ... that may be an overkill... simply - there can be a really lot of objects. — Igor
– Igor, Commented Feb 14, 2012 at 18:59

Peter Lawrey · Accepted Answer · 2012-02-14 19:14:39Z

3

Hundreds of 10 KB objects is still only a few MB. Keep it simple is my suggestion. Hundreds of thousands of 1 KB objects will still easily fit into a 32-bit JVM.

I wouldn't use an in memory database until you are getting into the GBs of data. If you have hundreds of GB, your only option is to use a database of some sort.

Disclaimer: I use in memory databases and have even written one or two.

answered Feb 14, 2012 at 19:14

Peter Lawrey

535k83 gold badges770 silver badges1.2k bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Bernd Elkemann · Accepted Answer · 2012-02-14 18:58:18Z

3

Try to do it with collections. If you then realize a problem you can still swich. It is all a matter of abstracting the implementation so your algorithms do not expect one or the other. (Yet another "early-optimization is evil" rant)

answered Feb 14, 2012 at 18:58

Bernd Elkemann

23.6k4 gold badges40 silver badges72 bronze badges

Comments

Kevin Welker · Accepted Answer · 2012-02-14 19:09:33Z

2

As others have said, "hundreds" is really not a lot, and now it sounds like you are even saying potentially less than hundreds. ANd if the heap size is a problem you can Increase the JVM Heap Size

answered Feb 14, 2012 at 19:09

Kevin Welker

7,9551 gold badge43 silver badges56 bronze badges

Collectives™ on Stack Overflow

Java Collections vs in-memory database performance

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related