RFR 8240704: CheckHandles.java failed "AssertionError: Handle use increased by more than 10 percent."

[Daniel Fuchs]

Hi Roger,

Looks good to me. If it were my own test I would add a little
Thread.sleep() after System.gc() to actually give time to the
gc to do something.

I have to note however that:

  83         final long ERROR_PERCENT = 10;
  84         final long ERROR_THRESHOLD = // 10% increase over min to 
passing max
  85                 startHandles + ((startHandles + ERROR_PERCENT - 1) 
/ ERROR_PERCENT);

is a bit misleading. IMO it only works because ERROR_PERCENT = 10; and
10 * 10 = 100; If you change it to ERROR_PERCENT = 1; for instance, then
you end up with allowing 100% of errors (and not 1%).

cheers,

-- daniel

On 11/03/2020 20:43, Roger Riggs wrote:
> Please review a test improvement to avoid counting unexpected handles.
> The test for 8239893[1]failed when non-test activities used handles.
> 
> The test is modified to do a warmup phase spawning some processes and 
> cleaning up.
> It then runs the test to create processes looking for no significant 
> increase in handles.
> The execution mode is limited to the interpreter to avoid potential side 
> effects of compilation.
> The error condition was corrected to look only for increases in the 
> number of handles.
> Previously, it looked for a 10% delta between the minimum and maximum 
> count of handles.
> 
> Webrev:
>      http://cr.openjdk.java.net/~rriggs/webrev-handlecount-8240704/
> 
> Issue:
>    https://bugs.openjdk.java.net/browse/JDK-8240704
> 
> Thanks, Roger
> 
> [1] 8239893 <https://bugs.openjdk.java.net/browse/JDK-8239893> Windows 
> handle Leak when starting processes using ProcessBuilder
>