Hi Yasumasa,
I just noticed that GcTest01.java and GcCauseTest03.java have also
failed for this reason. I see 9 total failures between the 3 tests so far.
On 5/4/18 6:17 AM, Yasumasa Suenaga wrote:
Hi Chris,
Thank you for your evaluation !
It is very helpful for me.
(I've not reproduced this issue on linux-x64 !)
It's just very intermittent.
I do not yet decided how do we fix this problem.
IMHO we can add fallback code to get raw PerfCounter data through
`jcmd PerfCounter.print`.
But I think we shouldn't be so because that fallback (jcmd) code might
hide jstat problem(s).
Also we cannot reproduce this issue completely, so we might not check
the change for this issue.
Do you have any idea?
As I pointed out in my initial review, this is not code I'm that
familiar with. One question I have is if it is even necessary to fail if
the value is .000? It seems the assumption is that if there was 1 GC
event, the total time spent will be at least .0005ms, rounded up to
.001ms, so it shows up in the output as a non-zero value. If that is the
case, maybe just drop the error check. Another option is to use
something other than .000 when the true value rounds to .000. Does it
have to be 3 digits? Maybe always print enough digits so you never end
up with all 0's.
thanks,
Chris
Thanks,
Yasumasa
On 2018/05/04 2:08, Chris Plummer wrote:
Hi Yasumasa,
Here are my results. I ran the test on macosx-x64-debug 500 times
using random machines. I saw the failure twice, both times on
different machines. I then ran 25 times on each of the 3 macosx
machines that have shown the failure, and did not see it again. So I
don't think this is necessarily an issue that is more likely to turn
up on one macosx machine than any other. It's just very intermittent.
I then ran 200 times each on all our supported platforms. So that
would be both debug and product builds on macosx, linux-x64,
solaris-sparc, and windows-x64. During those runs it turned up once
on linux-x64 (product, not debug), so this issue does not seem to be
limited to macosx.
best regards,
Chris
On 5/3/18 8:26 AM, Chris Plummer wrote:
Hi Yasumasa,
I only see the one reported failure in our recent test history for
this test, so it doesn't look like it happens every time. I'll try
running the test on the machine it failed on, both with the binary
it failed with and a more recent binary.
best regards,
chris
On 5/3/18 4:48 AM, Yasumasa Suenaga wrote:
FYI: jdk-11-ea+11 passed GcTest01.java
https://download.java.net/openjdk/testresults/11/archives/11/diff-hotspot-10-11.txt
On 2018/05/02 21:46, Yasumasa Suenaga wrote:
Hi all,
I've tried to fix 8202466, but I do not yet certain which solution
is the best for it.
So I want your opinion for it.
https://bugs.openjdk.java.net/browse/JDK-8202466
David reports serviceability/tmtools/jstat/GcTest01.java failed in
Mach5. It seems to appear on OS X only.
He has shared jtreg report, and I found as below:
```
stdout: S0C S1C S0U S1U EC EU OC OU MC MU CCSC CCSU YGC YGCT FGC
FGCT CGC CGCT GCT
0.0 0.0 0.0 0.0 3072.0 0.0 11264.0 2825.6 9472.0 9003.3 1024.0
845.3 26 0.204 3 0.292 1 0.000 0.497
```
YGCT: 0.204
FGCT: 0.292
CGCT: 0.000
GCT: 0.497
I guess this failure was caused by rounding error because (YGCT +
FGCT + CGCT) < GCT.
CGC is 1, so CGC operation might finish in very short time.
GcTest01.java:
http://hg.openjdk.java.net/jdk/jdk/file/4da7dce7e2bf/test/hotspot/jtreg/serviceability/tmtools/jstat/GcTest01.java#l57
GcCauseTest01.java:
http://hg.openjdk.java.net/jdk/jdk/file/4da7dce7e2bf/test/hotspot/jtreg/serviceability/tmtools/jstat/GcCauseTest01.java#l53
GcTest01 and GcCauseTest01 are very similar, but GcCauseTest01
passed.
Both tests use GcProvoker::provokeGc() to inflate memory usage. So
I wonder why GcTest01 just only failed.
I guess we might encounter similar issue(s) in the future if we
get more fast machines.
Hence I think we can take two approaches as below:
1. Add all tests in serviceability/tmtools/jstat to ProblemList.
2. Change all JstatGc*Tool to use custom jstat_options - to
show raw values in PerfCounters
What do you think?
I can start to work for it if they are OK.
Thanks,
Yasumasa
