RRF: JEP-271: Unified GC Logging
Bengt Rutisson
bengt.rutisson at oracle.com
Fri Nov 20 17:19:17 UTC 2015
Hi Stefan,
Thanks for looking at this!
On 2015-11-20 17:37, Stefan Johansson wrote:
> Hi Bengt,
>
> Overall I think the change is great, a few comments below.
>
> On 2015-11-19 16:29, Bengt Rutisson wrote:
>>
>> Hi everyone,
>>
>> After three pre-reviews it is time for the fist official review
>> request for JEP-271 Unified GC Logging.
>>
>> http://openjdk.java.net/jeps/271
>>
>> Most code changes are in the hotspot code:
>> http://cr.openjdk.java.net/~brutisso/JEP-271/review.00/webrev.00/
>>
> src/share/vm/prims/jvmtiEnv.cpp:
> 632 if (value == 0) {
> 633 LogConfiguration::parse_log_arguments("stdout", "gc", NULL,
> NULL, NULL);
> 634 } else {
> 635 LogConfiguration::parse_log_arguments("stdout", "gc=off",
> NULL, NULL, NULL);
> 636 }
>
> The condition should be changed to "value != 0" to get the same
> behavior as the old code.
Good catch! Will fix that.
I'll go through your comments regarding the tests below with David.
Thanks,
Bengt
>
> ---
> test/gc/arguments/TestTargetSurvivorRatioFlag:
> 217 // We found start of output emitted by
> -XX:+PrintTenuringDistribution
>
> Please update the comment to say "by -Xlog:gc+age=trace" instead.
>
> ---
> test/gc/arguments/TestVerifyBeforeAndAfterGCFlags.java:
> 45 // VerifyBeforeGC:[Verifying threads heap tenured eden syms
> strs zone dict metaspace chunks hand C-heap code cache ]
> 46 public static final String VERIFY_BEFORE_GC_PATTERN =
> "Verifying Before GC";
> 47 // VerifyBeforeGC: VerifyBeforeGC: VerifyBeforeGC:
> 48 public static final String VERIFY_BEFORE_GC_CORRUPTED_PATTERN
> = "VerifyBeforeGC:(?!\\[Verifying[^]]+\\])";
> 49
> 50 // VerifyAfterGC:[Verifying threads heap tenured eden syms
> strs zone dict metaspace chunks hand C-heap code cache ]
> 51 public static final String VERIFY_AFTER_GC_PATTERN =
> "Verifying After GC";
> 52 // VerifyAfterGC: VerifyAfterGC: VerifyAfterGC:
> 53 public static final String VERIFY_AFTER_GC_CORRUPTED_PATTERN
> = "VerifyAfterGC:(?!\\[Verifying[^]]+\\])";
>
> Please update the pattern comments to match the new logging better and
> maybe also remove the regexp parts of the corrupted pattern.
>
> 57 new String[] { "-Xlog:gc+verify=debug",
> 58 "-XX:+UseGCLogFileRotation",
>
> UseGCLogFileRotation has been removed and should be removed from the
> test as well.
>
> ---
> test/gc/ergonomics/TestDynamicNumberOfGCThreads.java:
> 52 // UseDynamicNumberOfGCThreads and TraceDynamicGCThreads enabled
>
> Comment should be changed to use -Xlog:gc+task=trace as well.
>
> ---
> While looking through the testing directories I found some additional
> changes that could be done.
>
> hotspot/test/testlibrary/jdk/test/lib/JDKToolLauncher.java:
> PrintGC and PrintGCDetails are used here and should be changed to use
> unified logging.
>
> hotspot/test/runtime/CommandLine/VMOptionsFile/optionfile_unmatched_quote_2:
>
> Xloggc is used here with an unmatched quote, so the test is fine but
> would be nice to change it to another X-option.
>
> ---
>
> I will take another round over the hotspot changes next week but so
> far everything else looks good.
>
>> Some tests in the JDK repo have been updated:
>> http://cr.openjdk.java.net/~brutisso/JEP-271/review.00/jdk-webrev.00/
>>
> JDK changes looks good.
>
> Thanks,
> Stefan
>
>> As with the pre-reviews I have put togther some examples of what the
>> new logging looks like:
>> http://cr.openjdk.java.net/~brutisso/JEP-271/review.00/compare.html
>>
>> The intent is that this should cover the bulk of the logging changes.
>> There will most definitely be some follow up changes where we fix
>> details in the log messages etc.
>>
>> Among many other old logging flags this changeset removes the two
>> flags PringGC and PrintGCDetails. These two will be added back with a
>> follow up changeset, but when they are added back they will be marked
>> as deprecated.
>>
>> The reason for first removing them and then adding them back is to
>> get testing without these flags. That way we will know that we clean
>> out all usages of these flags from our testing.
>>
>> Thanks,
>> Bengt
>
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