Out of Memory while putting in Disk Cache

[Flare Blitz]

I am trying to dump the data from a heap cache to disk cache via iterator, this happens every 30 mins. While trying to do that getting Out of Memory.
Note: Both heap and disk cache are created with ehcache as two separate caches.

Ehcache Version: 3.8.1
OS: Windows 10
JDK: ZuluJDK_8_0_322
Cache Configuration:

persistentCacheManager = (PersistentCacheManager) CacheManagerBuilder.newCacheManagerBuilder()
                                    .with(CacheManagerBuilder
                                            .persistence(ehCacheData.getDiskStoragePath()))
                                    .withCache(ehCacheData.getCacheName(), CacheConfigurationBuilder
                                            .newCacheConfigurationBuilder(String.class, ArrayList.class,
                                                    ResourcePoolsBuilder.newResourcePoolsBuilder()
                                                            .disk(450L, MemoryUnit.MB, true)))
                                    .build(true);

Code Snippet:
Iterator<Cache.Entry<String, ArrayList>> iterator = heapCache.iterator();
while (iterator.hasNext()) {
Cache.Entry entry = (Cache.Entry)iterator.next();
diskCache.put(entry.getKey(),entry.getValue());
}
heapCache.clear();

Exception Stack trace:
Failed to allocate direct buffer for FileChannel read.  Consider increasing the -XX:MaxDirectMemorySize property to allow enough space for the FileChannel transfer buffers|
Failed to allocate direct buffer for FileChannel read.  Consider increasing the -XX:MaxDirectMemorySize property to allow enough space for the FileChannel transfer buffers|
OutOfMemoryError Occurred::java.lang.OutOfMemoryError: Java heap space|
Thread::Thread[AnalyticsCacheDumpThread,5,main]|

Found the below exception later while trying to get from the cache:
Ehcache key xxxxxxxxxxxx.xxxxxx-x-x-xx-xxxxxxxxxx-xxxxxxxxx-xxxxxxxxxx-xxxx in possible inconsistent state - Similar messages will be suppressed for 30 seconds|
org.ehcache.spi.resilience.StoreAccessException: java.lang.RuntimeException: java.io.EOFException
at org.ehcache.core.exceptions.StorePassThroughException.handleException(StorePassThroughException.java:78)
at org.ehcache.impl.internal.store.offheap.AbstractOffHeapStore.internalGet(AbstractOffHeapStore.java:211)
at org.ehcache.impl.internal.store.offheap.AbstractOffHeapStore.containsKey(AbstractOffHeapStore.java:219)
at org.ehcache.core.EhcacheBase.containsKey(EhcacheBase.java:220)
XXXXXXXXXXXX...........................................

Caused by: java.lang.RuntimeException: java.io.EOFException
at org.ehcache.shadow.org.terracotta.offheapstore.disk.storage.FileBackedStorageEngine$FileChunk.readBuffer(FileBackedStorageEngine.java:601)
at org.ehcache.shadow.org.terracotta.offheapstore.disk.storage.FileBackedStorageEngine$FileChunk.readKeyBuffer(FileBackedStorageEngine.java:534)
at org.ehcache.shadow.org.terracotta.offheapstore.disk.storage.FileBackedStorageEngine.readKeyBuffer(FileBackedStorageEngine.java:265)
at org.ehcache.shadow.org.terracotta.offheapstore.storage.PortabilityBasedStorageEngine.equalsKey(PortabilityBasedStorageEngine.java:125)
at org.ehcache.shadow.org.terracotta.offheapstore.OffHeapHashMap.keyEquals(OffHeapHashMap.java:1005)
at org.ehcache.shadow.org.terracotta.offheapstore.OffHeapHashMap.computeIfPresentWithMetadata(OffHeapHashMap.java:2101)
at org.ehcache.shadow.org.terracotta.offheapstore.AbstractLockedOffHeapHashMap.computeIfPresentWithMetadata(AbstractLockedOffHeapHashMap.java:542)
at org.ehcache.shadow.org.terracotta.offheapstore.concurrent.AbstractConcurrentOffHeapMap.computeIfPresentWithMetadata(AbstractConcurrentOffHeapMap.java:781)
at org.ehcache.impl.internal.store.disk.EhcachePersistentConcurrentOffHeapClockCache.computeIfPresent(EhcachePersistentConcurrentOffHeapClockCache.java:175)
at org.ehcache.impl.internal.store.offheap.AbstractOffHeapStore.internalGet(AbstractOffHeapStore.java:184)
... 11 more
Caused by: java.io.EOFException
at org.ehcache.shadow.org.terracotta.offheapstore.disk.storage.FileBackedStorageEngine$FileChunk.readBuffer(FileBackedStorageEngine.java:594)
... 20 more

Kindly help me regarding this. Thank you.