Lease expiring pre-maturely?

Question

Hello all. I am having a problem with the lease expiring "early". What I mean by "early" is that in the log files, I can see, under normal runtime behavior, the leases are getting renewed on time (half of what I set java.rmi.dgc.leaseValue to , which is currently 60000). This means that approximately every 30000 ms, a lease renewal should be issued from the client. However, for some unexplained reason yet, on occassion, the client "pauses" in it's request for renewals (which I read as "dirty" DGCImpl requests), and when it does issue another renewal, it is beyond the lease time, and thus, the lease expires on the server, the dgc cleans up the object, and life sucks ;) I am including some of the relavent pieces from the RMI debug logs, to see if any of you RMI experts out there can help me out with this one. Perhaps I am doing something stupid, but it also happens if I use all the RMI default settings (leaseValue=300000).
The sun.rmi.dgc log:
Normall, it looks like this:
May 6, 2005 8:27:35 AM sun.rmi.transport.DGCImpl dirty
FINER: RMI TCP Connection(140)-10.1.1.118: vmid = dc272e433df044f5:-76cb1e61:103af2ee3f1:-7ffe
May 6, 2005 8:28:05 AM sun.rmi.transport.DGCImpl dirty
FINER: RMI TCP Connection(140)-10.1.1.118: vmid = dc272e433df044f5:-76cb1e61:103af2ee3f1:-7ffe
(notice, that the renewal took exactly 30 seconds.. 1/2 of the 60 second lease value). However, after running for what seems to be about 12 minutes, the lease requests are screwed up:
May 6, 2005 8:31:26 AM sun.rmi.transport.DGCImpl dirty
FINER: RMI TCP Connection(210)-10.1.1.118: vmid = dc272e433df044f5:22d2d60a:103af2f381c:-7ffe
May 6, 2005 8:32:47 AM sun.rmi.transport.DGCImpl dirty
FINER: RMI TCP Connection(210)-10.1.1.118: vmid = dc272e433df044f5:22d2d60a:103af2f381c:-7ffe
The lease request to renew took too long: 81 seconds (almost 3 times what it should have been). At this point, the lease is expired (between the above two messages):
May 6, 2005 8:32:47 AM sun.rmi.transport.DGCImpl$LeaseInfo expired
FINE: RMI LeaseChecker: dc272e433df044f5:22d2d60a:103af2f381c:-7ffe
At which point, my Remote object gets dereferenced:
May 6, 2005 8:32:47 AM sun.rmi.transport.Target vmidDead
FINE: RMI LeaseChecker: removing endpoint dc272e433df044f5:22d2d60a:103af2f381c:-7ffe from reference set
May 6, 2005 8:32:47 AM sun.rmi.transport.Target refSetRemove
FINER: RMI LeaseChecker: reference set is empty: target = sun.rmi.transport.Target@9f05b80
Any ideas on why this is happening? How can I make the client make it's requests in a more timely manner (the server and client are only two rooms away from each other, so they are not traversing the planet).
Thanks!

Answer 1

I recommend you ask this on the RMI-USERS mailing list (which you would have to join - see the bottom of the RMI Guide to Features in your JDK). That way you will get the attention of Sun employees.
EJP