Hi Daniil,
I agree with Chris below.
Will tell more on reply to your reply.
Thanks,
Serguei
On 11/2/18 20:59, Chris Plummer wrote:
Hi Daniil,
I thought the issue was that C2 was doing metadata allocations, and
when it ran out of metaspace it did a GC (one that was not triggered
by a failed object allocation). As a results we were getting objects
GCs before the test ever got the chance to disable collection on them.
I thought we also concluded other than this metaspace issue, if the
test is properly disabling collection on the objects it cared about,
it shouldn't matter if there are GC's triggered by excessive object
allocations.
I don't think the following check will always be valid. It may be on
by default at some point:
651 public boolean isJVMCICompilerOn() {
652 String opts = argumentHandler.getLaunchOptions();
653 return opts.indexOf("-XX:+UseJVMCICompiler") >= 0;
654 }
thanks,
Chris
On 11/2/18 4:29 PM, Daniil Titov wrote:
Please review the change that fixes several tests failing with
com.sun.jdi.ObjectCollectedException when running with Graal.
There main problem here is that with Graal on JVMCI Compiler threads
in the target VM create a lot of objects and sporadically trigger GC
that results in the objects created in the target VM in the tests
being GCed before the tests complete. The other problem is that for
some classes the tests use, e.g. "java.lang.String", there is
already a huge number of instances created by JVMCI threads.
The fix suspends target VM to prevent JVMCI compiler threads from
creating new objects during the tests execution. In cases when IOPipe
is used for communication between the test and the debuggee the fix
suspends all threads but the main rather than suspending the VM. The
fix also filters out the checks for some test classes (e.g.
"java.lang.String") in cases when the target VM is run with JVMCI
compiler options on.
Webrev: http://cr.openjdk.java.net/~dtitov/8203174/webrev.01/
Bug: https://bugs.openjdk.java.net/browse/JDK-8203174
Thanks,
Daniil
