Terracotta Discussion Forums (LEGACY READ-ONLY ARCHIVE)

- Terracotta 3.5.0
- Java 1.6.0_29
- Tomcat 6.x

Our app fails to start and the client log has:

Error occurred during initialization of VM
java.lang.NoSuchMethodError: java.util.LinkedHashMap$Entry.<init>(ILjava/lang/Object;Ljava/lang/Object;Ljava/util/HashMap$Entry;)V
at java.util.LinkedHashMap.init(Unknown Source)
at java.util.HashMap.<init>(Unknown Source)
at java.util.LinkedHashMap.<init>(Unknown Source)
at java.io.ExpiringCache$1.<init>(ExpiringCache.java:47)
at java.io.ExpiringCache.<init>(ExpiringCache.java:47)
at java.io.ExpiringCache.<init>(ExpiringCache.java:42)
at java.io.UnixFileSystem.<init>(UnixFileSystem.java:127)
at java.io.FileSystem.getFileSystem(Native Method)
at java.io.File.<clinit>(File.java:127)
at java.lang.Runtime.loadLibrary0(Runtime.java:819)
at java.lang.System.loadLibrary(System.java:1028)
at java.lang.System.initializeSystemClass(System.java:1086)

It turns out this is caused by using -XX:+AggressiveOpts which (according to this posting https://wiki.shibboleth.net/confluence/display/SHIB2/IdPClusterIssues) enables the experimental TreeMap added in 1.6.0_14

Is there a plan to support that TreeMap implementation?

The shibboleth team is using an older integration mechanism to Terracotta. Discussions have led to the conclusion that Ehcache-based integration instead of direct clustered collection support would be a better way to go. But no work is being done on the new integration concept.

So no, Treemap is not going to be supported any time soon. Unfortunately, I think the Shibboleth team plan to cluster using another technology go forward and that message is taking time to permeate the community.

Sorry for the bad news :(

Feel free to press them to work with Ehcache as these sorts of tight-coupling and fragile implementation issues go away if Shibboleth changes the Terracotta implementation approach just a bit.

--Ari

We are NOT using Shibboleth; our application is clustered using straight DSO clustered collections, etc, it was their post that pointed me to the root cause. The aggressive opts are actually appealing to us in a couple of specific cases/customer work loads, so supporting TreeMap would allow us to run those customers on clusters AND use the aggressive opts

Not sure I understand.

Not using Shibboleth, I get.

But are you saying you need TreeMap whether or not -XX:... works?

TreeMap experimental impl from 1.6.x support in DSO is definitely not gonna get added any time soon based on what I heard from TC guys. Can you work around the issues w/ what you get in off-the-shelf DSO as is?

--Ari