RFR(S): 8221350 more monitor logging updates from Async Monitor Deflation project

[David Holmes]

Hi Dan,

On 23/03/2019 6:23 am, Daniel D. Daugherty wrote:
> Greetings,
> 
> I have a (S)mall patch extracted from the Async Monitor Deflation project
> that is ready for code review.
> 
> The short version of what this patch is about:
> 
>      More monitor logging updates.
> 
> The details are in the bug report:
> 
>      JDK-8221350  monitor logging updates from Async Monitor Deflation 
> project
> https://bugs.openjdk.java.net/browse/JDK-8221350
> 
> Here's the webrev:
> 
> http://cr.openjdk.java.net/~dcubed/8221350-webrev/3-for-jdk13.more_monitor_logging/ 

This mostly seems okay. One comment on the timer changes in 
synchronizer.cpp. Why not just change this:

1711   timer.stop();
1712
1713   Thread::muxAcquire(&gListLock, "deflate_thread_local_monitors");
1714
1715   // Adjust counters
1716   counters->nInCirculation += thread->omInUseCount;
1717   thread->omInUseCount -= deflated_count;
1718   counters->nScavenged += deflated_count;
1719   counters->nInuse += thread->omInUseCount;
1720   counters->perThreadScavenged += deflated_count;
1721   // For now, we only care about cumulative per-thread deflation time.
1722   counters->perThreadTimes += timer.seconds();

to move the timer.stop() to after line 1720, rather than moving outside 
the mux-block and reacquiring the mux again?

Thanks,
David
-----

> 
> This patch along with the current patch for Async Monitor Deflation
> project have been through Mach5 tier[1-8] testing.
> 
> I have been actively using this new logging code while debugging and
> analyzing my port of the Async Monitor Deflation project code.
> 
> Thanks, in advance, for any questions, comments or suggestions.
> 
> Dan