A better ehcache.xml configuration file for the Play Framework, which out of the box limits the size of the cache based on the number of objects you put in it rather than the number of bytes. I personally think that's not a very smart choice. Also see http://ehcache.org/documentation/2.5/configuration/cache-size#cache-configuration-sizing-attrib…

ehcache.xml

<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../config/ehcache.xsd" updateCheck="false">

    <!-- This is a default configuration for 256Mb of cached data using the JVM's heap, but it must be adjusted
         according to specific requirement and heap sizes -->

    <defaultCache
            maxBytesLocalHeap="256000000"
            eternal="false"
            timeToIdleSeconds="120"
            timeToLiveSeconds="120"
            overflowToDisk="false"
            maxElementsOnDisk="10000000"
            diskPersistent="false"
            diskExpiryThreadIntervalSeconds="120"
            memoryStoreEvictionPolicy="LRU"
    /> 
    
</ehcache>