Re: RFR: JDK-8036026: nsk/jvmti/scenarios/capability/CM02/cm02t001 fails intermittently

[Gary Adams]

Patch attached.

I think one reviewer is sufficient for a trivial patch.

On 10/3/18, 4:49 PM, Chris Plummer wrote:

Hi Gary,

Although I don't like relying on timer delays for stuff like this, the code for it is already in place, so I'm ok with making the delay longer to make sure there is contention on the monitor. Could you update the comment to read "// pause to provoke contention on thread.endingMonitor"

thanks,

Chris

On 10/3/18 11:55 AM, Gary Adams wrote:

While running a block of nsk/jvmti/scenarios tests, I noticed an occasional failure

for cm02t001 in windows debug platform. After enabling the nsk verbose
diagnostics and adding a few messages in the main test and the debuggee

thread, it became clear that the missing contention was due to the main thread

getting ahead of the debugee thread.

The call to letFinish() below let's the deuggee thread wake up from it's wait

and proceed to the contention for the endingMonitor. If the main thread

waits a little longer it should reach the debuggee thread synchronized block.

I reopened an earlier bug that was closed as CNR.

  Issue: https://bugs.openjdk.java.net/browse/JDK-8036026

diff --git a/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java b/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java --- a/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java +++ b/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java

@@ -82,7 +82,7 @@
                 thread.letFinish();

                 // pause to provoke contention
-                Thread.sleep(100);
+                Thread.sleep(1000);
             } catch (InterruptedException e) {
                 throw new Failure(e);
             }

# HG changeset patch
# User gadams
# Date 1538651169 14400
#      Thu Oct 04 07:06:09 2018 -0400
# Node ID 1c8f7e6624048bc1c20d836661ed4834920fb038
# Parent  82dc590fa5864aa22f54bc9a834287bf81b4c35a
8210337: runtime/NMT/VirtualAllocTestType.java failed on RuntimeException 
missing from stdout/stderr
Reviewed-by: cjplummer

diff --git 
a/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java
 
b/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java
--- 
a/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java
+++ 
b/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/capability/CM02/cm02t001.java
@@ -81,8 +81,8 @@
                     return status;
                 thread.letFinish();
 
-                // pause to provoke contention
-                Thread.sleep(100);
+                // pause to provoke contention on thread.endingMonitor
+                Thread.sleep(1000);
             } catch (InterruptedException e) {
                 throw new Failure(e);
             }