Hi Found new webrev here: http://cr.openjdk.java.net/~lmesnik/8203491/webrev.01/ <http://cr.openjdk.java.net/~lmesnik/8203491/webrev.01/> and inc diff http://cr.openjdk.java.net/~lmesnik/8203491/webrev.01-00/ <http://cr.openjdk.java.net/~lmesnik/8203491/webrev.01-00/>
I don't know if existing 64m is enough to produce a lot of classes. However this size was used in original test so I use same in new test TestJmapCoreMetaspace.java. I fixed comments, import and timeout(set to 240) also. Leonid > On May 24, 2018, at 9:16 AM, Jini George <jini.geo...@oracle.com> wrote: > > Hi Leonid, > > My comments inline. > > On 5/24/2018 12:09 AM, Leonid Mesnik wrote: > >> I am not sure that JMapMetaspaceCore provides any additional coverage. The >> test just fill 64M of metaspace and then send signal to dump core. So I >> don't see how this test could improve coverage. >> I think that idea of original test was to fill PermGen like Heap to expand >> it as much as possible or it was just an analog of test >> OnOOMToFileMetaspace. While current test just fill highly limited metaspace. >> So number of classes seems to be not significantly larger then for current >> TestJmapCore.java test. From my point of view it would be make a sense to >> generate dump containing a lot of loaded classes or some very large classes. >> While current test looks pretty similar to existing TestJmapCore.java test. >> Please let me know if you see the test scenario when such test could be >> useful. > > From what I can make out, EatMemory with -metaspace would create a lot of > loaded classes with GeneratedClassProducer. And this could provide some good > testing for writeClassDumpRecords() of HeapHprofBinWriter. Let me know if you > think I have overlooked something. > > >>> * You might want to increase the timeout factor for this test. The test >>> times out on my machine. >>> >>> >> I see that test finishes in 1 minute in our lab while. I see that it takes >> 30 seconds on 2CPU Oracle Linux VM with 2GB java heap. And test just fails >> with JDK-8176557 when I increase heap. >> How many time it takes on you machine? The timeoutFactor might be used for >> untypical environment/command-line options. > > It took about 130 secs a couple of times. Don't know if it was an anomaly. > >>> * You might want to consider removing the corefile and the heapdump files >>> after the test execution (in the cases where the test passes). >>> >> The default jtreg retain policy in make files just removes all files in test >> directory for passed tests. The jtreg default test policy says >> "If -retain is not specified, only the files from the last test executed >> will be retained". >> So it should be not a problem in most of cases. While there is no way for >> user to retain core/heapdump files even if user wants to keeps them. > > Ok. > >> However if it is the common rule for sa tests to delete such artifacts then >> I could remove heap/core dumps. >>> >>> One suggestion is to check if /proc/sys/kernel/core_pattern has a line >>> starting with '|' and print a warning that a crash reporting tool might be >>> used (Something like in ClhsdbCDSCore.java). But it is just a suggestion >>> and you are free to ignore it. In due course, we could include this test >>> also as a part of the consolidation of SA's corefile testing effort >>> (https://bugs.openjdk.java.net/browse/JDK-8202297). >>> >> I would prefer to left this improvement for JDK-8202297. I think good core >> dump processing/ulimit settings requires more efforts and testing and >> different version of Linux. (Might be even for Non-Oracle platforms). >> Also logic in test ClhsdbCDSCore.java is slightly different. It tries to get >> possible core location from hs_err file and print this hint of core file >> from hs_err doesn't exists. While printing this hint if core dumps are just >> completely disabled might just confuse users. > Sounds fine. > > Thanks, > Jini.