Showing posts from December, 2006

Java 5 crash - the saga continues

It really seems to be a problem related to the GC options mentioned here . However there seems to be more to it. With the rather aggressive setting of only 6 seconds between full GCs we were able to reproduce the problem, however only on a very specific combination of hardware, OS and Java VM. Running on RedHat 9 with Sun's Java VM 1.5.0_09 we could only see the problem on one machine that appears to be the same as all the others we use. However as this very same machine shows no problems at all when running our application with Java 1.4.2_08 or 1.6.0RC - even with the 6 seconds interval - I do not believe in faulty hardware. I removed the machine's hard drive and put it into an identical system (as far as we can see and are told by its manufacturer). In that box (and two more I tried) I cannot get any crash with either Java 1.4, 1.5 or 1.6. Strangely enough even the drive from one of those other machines mounted into the problematic box showed no problems. We really do not h

Some progress on Java 5 on Linux crash

In two previous posts ( first here and second here ) I reported about Java 5 VM crashes on Linux machines. Digging deeper into the problem with external support led to some new evidence. Apparently the problem is in some way related to regular garbage collects initiated by the so called "GC Daemon" thread. It gets spawned when you use some fashion or other of RMI and calls full GCs in order to get rid of unreachable remote objects. One can specify the interval (in milliseconds) between calls to the garbage collector using -Dsun.rmi.dgc.server|client.gcInterval . With our application using RMI to call remote services we reduced this value to as little as 6 seconds. As we expected this let us reproduce the problem we have much more often than before. In 4 days we observed 8 VM crashes, each of them with very similar hs_err files. This means that my test program might have revealed even another bug, because it did produce some crashes, however it does not use anything conne

Follow Up: F-Secure's response

Not too long ago I wrote about a problem concerning F-Secure Anti-Virus 2007 and the Kerio Personal Firewall in this article. At the end of it I said I would inform F-Secure about the problem. I did and this is about their response. On November 13th I used the support form on F-Secure's website (Germany) to report to them the problem I had experienced. My report was about 2K long (I still have it) and included precise information about the situation, what I had found out and what to do to prevent it. I suggested having the installer issue a warning concerning 3rd party personal firewalls, especially since those seemed to be no problem with the 2006 version. I also included a link to my even more verbose blog post . On November 14th I got a response from one of their support agents. Apart from a lengthy auto-generated intro on how to issue correct problem reports (comes with every mail, does not have anything to do with your individual request) I got a very brief answer (I transl