Hazelcast Threading behaviour for IMap and MapLoader

[Harish Gupta]

Does Hazelcast MapLoader uses partition threads to execute the MapLoader implementations [ loadAllKeys(), loadAll(keys) ] and other partition operations like IMap.get(key), IMap.put(K, V) ?

As we want to control the thread count for Initial Map loading and other map operations separately.

Also, suggest ways to control these thread counts.

[Jiri Holusa]

Hi Harish,

I know that this is an old question, but let me answer it for the sake of future people.

Up to Hazelcast Platform 5.2, the MapLoader/Store operations are executed on the partition threads, same as other partition operations such as IMap.get etc. That means that the MapLoader loading blocks the clients and all the other operations.

In 5.2, we're finally implementing offloading of those operations to a separate thread pool, so it will no longer block.

Hope that helps somebody,

Jiri