Oracle Coherence memory usage, indexes

In previous posts we discussed a memory consumption in Oracle Coherence. We loaded 1M of DomainObj into cached and looked into memory dumps aquired with jmap utility. Now, we will talk about memory overheads caused by another powerful feature of Coherence - indexes.

Full text of article is available at GridDynamics blog - http://blog.griddynamics.com/2009/10/coherence-memory-usage-indexes.html

Oracle Coherence memory usage, structure of cache

Imagine that you are working on project involving an in-memory data grid. You have analyzed your requirements and you can see that you need to store 10 million objects in your grid. The next question is how much physical memory do you need to provide such capacity? I recently have been facing the same question, and want to share some findings about how Oracle Coherence (popular in-memory data grid middleware) uses memory.

Full text of article is available at GridDynamics blog - http://blog.griddynamics.com/2009/09/oracle-coherence-memory-structure-of.html

Oracle Coherence using POF, without a single line of code

People developing distributed Java applications know the importance of wire formats for objects. Native Java serialization has only one advantage—it is built in. It is relatively slow, not very compact, and has other quirks. Starting with version 3.2, Oracle Coherence is offering its own proprietary binary wire format for objects—POF serialization. POF is not only cross platform, but also much more compact and faster compared to built-in serialization. Both compactness and speed are extremely important for data grid application. The only disadvantage of POF is that you should write custom serialization/deserialization code for each of your mobile objects. Not only domain objects stored in cache should have serializers, but also entry processors, aggregators, etc. The amount of code you have to write may look daunting and force you to stick with built-in Java serialization.

Full text of article is available at GridDynamics blog - http://blog.griddynamics.com/2009/09/oracle-coherence-using-pof-without.html