Infinispan 7.2.0.Beta2 released with better default configuration handling

We've just released Infinispan 7.2.0.Beta2 which adds better support for determining which configuration options have been defined by the user versus those options that contain default values. This is an important stepping stone in our aim to enable partial configuration overlays and proper configuration template support.

On top of that, we've added the capability for Java Hot Rod clients to recover from full cluster restarts and fixed an important topology transfer bug that lead to ArrayIndexOutOfBoundsException exceptions when applying topology changes.

Finally, in order to provide better out-of-the-box experience with Near Caches in Java Hot Rod client, we have made mandatory to define the maximum number of entries Near Caches should have. Previously, Near Caches were configured to be unbounded by default which would have resulted in memory leaks unless the client removed them by calling RemoteCache.remove() or similar. A configuration exceptions is reported now if no maximum size has been defined in the Java Hot Rod client, but the user can still provide a 0 or negative value to indicate the Near Caches should be unbounded.

For a complete list of features and bug fixes included in this release, please refer to the release notes.  

Feel free to join us and shape the future releases on our forums, our mailing lists or our #infinispan IRC channel.

Cheers,

Galder

Eviction Improvements in Infinispan 7.2.0.Beta1

As many of you are most likely aware Infinispan provides a way to limit how many entries are stored in a single node's memory at a given time.  This is configurable via the eviction element in xml or EvictionConfiguraitonBuilder through the programmatic configuration.

In 7.2.0.Beta1 we have made some internal changes to our internal eviction support.  This mostly entailed moving our implementation to the new ConcurrentHashMap that was updated for Java 8.  This provides for a few new benefits and behaviors.

Long Size Support

Previously our eviction entry amount was limited to the maximum value of an int (2^31) and was always rounded up to the nearest power of 2 (ie. 100 would be changed to 128 which is 2^7).

With the new changes you can store up to a long worth of entries and it is not constrained to a power of 2.  Unfortunately Beta1 does not contain the changes to allow for a long to be configured yet, but this should be fixed before 7.2.0.Final is done.

Memory wide eviction size

The old bounded map performed it's eviction based on evicting elements stored in the same segment.  This could cause the map to evict entries before it actually hit the maximum size.  This is described in detail here.

The new ConcurrentHashMap for Java 8 automatically resizes its number of segments.  As such the old method of eviction will not work.  Instead we keep track of all entries in the entire map and only evict when we go over the max size.  This prevents entries from being evicted that may not be the the least recent (previously in the case of when many elements in the same segment were added).

Better scalability

Since we utilize the new ConcurrentHashMap this automatically resizes the segments based on the amount of entries in the cache.  Increasing the number of segments has some various benefits.

Less blocking

With more segments, that means there is more fine grained locking when updating an entry.  The determination whether an entry needs evicting is done outside of any lock, further reducing contention.

Lower time complexity

Since there are more segments there should be fewer hash collisions, which should provide O(1) complexity much more frequently for accessing a given key.

Cheers,

Will

Infinispan 7.2.0.Beta1 released

Dear Infinispan community,

We are proud to announce the release of Infinispan 7.2.0.Beta1 today.

Along the usual assortment of bug fixes, this release includes a few exciting new features:

• Server-side scripting with JSR-223 (ISPN-5013)
• Initial support for the JCache API over HotRod (ISPN-4955)
• Improved size-based eviction, implemented on top of Doug Lea's ConcurrentHashMapV8 (ISPN-3023)

For a complete list of features and bug fixes included in this release, please refer to the release notes.  

Feel free to join us and shape the future releases on our forums, our mailing lists or our #infinispan IRC channel.

Many thanks to everyone who contributed to this release!