Terracotta Discussion Forums (LEGACY READ-ONLY ARCHIVE)

Hi,

It would be helpful if you can give me the solution for this.

Concern is : I am trying to persist the data to the disk and loading on server startup. .data file is getting created but there is no .index file created anywhere. On reading of the cache after server startup, there are no elements in cache.

My ehcache.xml file as below:
--------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="ehcache.xsd" >
<diskStore path="C:\work\Hazmat\cacheBackup"/>
<cache name="items" maxElementsInMemory="10000" maxEntriesLocalHeap="10000" eternal="true" timeToIdleSeconds="0"
timeToLiveSeconds="0" overflowToDisk="false" clearOnFlush="true" memoryStoreEvictionPolicy="LRU" diskPersistent="true" >
<bootstrapCacheLoaderFactory
class="net.sf.ehcache.store.DiskStoreBootstrapCacheLoaderFactory"
properties="bootstrapAsynchronously=true"/>
</cache>
</ehcache>
------------------------------------------

My web.xml (Using Tomcat6) contains below configuration:

<listener>
<listener-class>net.sf.ehcache.constructs.web.ShutdownListener</listener-class>
</listener>

------------------------------------------------------
I am creating cache as below:

CacheManager manager = CacheManager.create(CACHE_CONFIG_FILE);
System.out.println("manager instance is : "+manager);

System.out.println("is cache exists:"+manager.cacheExists("items"));

this.cache = manager.getCache("items");

-----------------------------------------------------------------------

Am I doing anything wrong anywhere? Please suggest.

Can you try again with overflowToDisk=true alongwith diskPersistent="true" setting. Also in your ehcache.xml I see

maxElementsInMemory="10000" maxEntriesLocalHeap="10000

Both are same thing why are you defining this twice.

Plus, AFAIK, contents are persisted to disk only when you perform a cacheManager.shutdown.

Tahank you for responding to my issue.

1. I tried with the option overflowToDisk=true (also mentioning only this attribute maxElementsInMemory="10000"), still it didn't work.

2. I am configuring shutdown manager in the web.xml and also java class like below:
System.setProperty("net.sf.ehcache.enableShutdownHook", "true");

3) items.data file is getting created but not the items.index file.

4) In logs it gives the following message.
net.sf.ehcache.store.disk.Segment.put(Segment.java:420)evel [http-8585-2hread] - put added 0 on heap

Please help me with your thoughts.

Not sure why this is so complex. Setting the system property for the shutdown hook will not help. You need to manually shutdown your cacheManager for the contents to be persisted.
Anyways, Good Luck!

Thanks Karthik.

I found the issue, why it is not creating the .index file. This file got created when i called explicitly cache.flush() . Then it started working. But just want to know, If I call flush method, will there be any performance overhead?

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