RFR (S): 7176220 'Full GC' events miss date stamp information occasionally

[Jon Masamitsu]

Andreas,

Thanks.  That log parse fine.  Please do a second with "-XX:+PrintGCDetails"

Jon

On 5/15/2013 4:41 AM, Andreas Eriksson wrote:
> Hi,
>
> The format of the regular logs should be the same as before.
>
> A sample of how they look after the change with the default GC is 
> attached (running ./hsx24_hotspot-build/bin/java -Xmx2m -verbose:gc 
> -XX:+PrintGCTimeStamps -XX:+PrintGCDateStamps -Xloggc:gc.log 
> HumongousAlloc)
>
> Please let me know if you need me to run with any other flags or some 
> other java program.
>
> /Andreas
>
> On 2013-05-15 06:57, Jon Masamitsu wrote:
>> Andreas,
>>
>> Please send a short sample of a new log.  I want to see if
>> our log parsers work on the new log.  If you have not already
>> done so, please do not push this until I've checked that the
>> logs still parse.
>>
>> Jon
>>
>> On 5/14/2013 2:21 AM, Andreas Eriksson wrote:
>>> Hi,
>>>
>>> I changed the date and time stamping calls to use the guarded 
>>> convenience variants.
>>> Both of these calls suffixes a ": " automatically. See 
>>> share/vm/utilities/ostream.hpp line 99 and 105.
>>>
>>> It currently looks like this:
>>> % ./hsx24_hotspot-build/bin/java -Xmx2m -verbose:gc 
>>> -XX:+PrintGCTimeStamps -XX:+PrintGCDateStamps HumongousAlloc
>>> 2013-05-14T11:17:28.340+0200: 0.050: [GC 1896K->421K(3136K), 
>>> 0.0011640 secs]
>>> 2013-05-14T11:17:28.341+0200: 0.051: [GC 2329K->437K(3136K), 
>>> 0.0029750 secs]
>>>
>>> This is how it looked before as well:
>>> % ~/builds/linux-amd64/7u25/bin/java -Xmx2m -verbose:gc 
>>> -XX:+PrintGCTimeStamps -XX:+PrintGCDateStamps HumongousAlloc
>>> 2013-05-14T11:17:31.603+0200: 0.059: [GC 2025K->417K(3136K), 
>>> 0.0008100 secs]
>>> 2013-05-14T11:17:31.605+0200: 0.060: [GC 2325K->417K(3136K), 
>>> 0.0015140 secs]
>>>
>>> Thanks for looking at this.
>>>
>>> /Andreas
>>>
>>> On 2013-05-14 08:23, Bengt Rutisson wrote:
>>>>
>>>> Hi Andreas,
>>>>
>>>> Looks good.
>>>>
>>>> One question regarding the change in GCTraceTime:
>>>>
>>>> http://cr.openjdk.java.net/~aeriksso/7176220/webrev.00/src/share/vm/gc_implementation/shared/gcTraceTime.cpp.udiff.html 
>>>>
>>>>
>>>> It looks to me like we are missing a ": " in the new version. Maybe 
>>>> it is ok to loose this character in the log format, but a safer 
>>>> change may be:
>>>>
>>>> if (PrintGCTimeStamps || PrintGCDateStamps) {
>>>>   gclog_or_tty->date_stamp(PrintGCDateStamps);
>>>>   gclog_or_tty->stamp(PrintGCTimeStamps);
>>>> gclog_or_tty->print(": ");
>>>> }
>>>>
>>>> This actually still changes the ": " behavior since since you 
>>>> didn't use to get a ": " if you only had PrintGCDateStamps enabled. 
>>>> But I think this is a more expected behavior.
>>>>
>>>> Thanks,
>>>> Bengt
>>>>
>>>> On 5/13/13 6:01 PM, Andreas Eriksson wrote:
>>>>> Hi all,
>>>>>
>>>>> Please take a look at my changes for bug 7176220.
>>>>> The problem is that CMS sometimes misses datestamps for time trace 
>>>>> printouts.
>>>>>
>>>>> The proposed fix is to move the datestamp print logic into the 
>>>>> class that handles time trace printouts, GCTraceTime.
>>>>> This would make it consistent with timestamps, which are already 
>>>>> printed from there.
>>>>>
>>>>> Bugs.sun:
>>>>> http://bugs.sun.com/view_bug.do?bug_id=7176220
>>>>>
>>>>> JIRA:
>>>>> https://jbs.oracle.com/bugs/browse/JDK-7176220
>>>>>
>>>>> Webrev:
>>>>> http://cr.openjdk.java.net/~aeriksso/7176220/webrev.00/
>>>>>
>>>>> Testing:
>>>>> jprt, jtreg
>>>>>
>>>>> Thanks,
>>>>> Andreas
>>>>>
>>>>
>>>
>>>
>>
>