RFR: 8139564: Convert TraceDefaultMethods to Unified Logging

[harold seigel]

Hi Rachael,

The code looks good.

One comment about this FOR loop in defaultMethods.cpp:

      686     for (int i = 0; i < slots->length(); ++i) {
    687 ResourceMark rm;
    688 outputStream* logstream = LogHandle(defaultmethods)::debug_stream();
    689 streamIndentor si(logstream);
    690 logstream->indent();
    691 slots->at(i)->print_on(logstream);
    692 logstream->cr();
      693     }

Can you move lines 687-689 above the loop so that they only get executed 
once per FOR loop, instead of every iteration?


Also, you may not need the ResourceMark at line 831 because there is one 
at line 809.

    830 if (log_is_enabled(Debug, defaultmethods)) {
    831 ResourceMark rm;
    832 outputStream* logstream = LogHandle(defaultmethods)::debug_stream();
    833 streamIndentor si(logstream, 2);
    834 logstream->indent().print("Looking for default methods for slot ");
    835 slot->print_on(logstream);
    836 logstream->cr();


Finally, is the ResourceMark needed at line 940?

Thanks, Harold

On 10/15/2015 6:33 PM, Ioi Lam wrote:
>
>
> On 10/15/15 10:51 AM, Rachel Protacio wrote:
>> Hi, Ioi,
>>
>> Thanks for the comments. While all valid points, the decision by the 
>> serviceability team with regards to the logging framework as a whole 
>> is to move all the output to product mode. Because of this, I ran 
>> performance tests to make sure that the newly-introduced product code 
>> will not slow it down. So yes, all the "#ifndef PRODUCT" sections 
>> that are necessary for this logging have been liberated to product mode.
>>
> Thanks Rachel. This makes sense.
>
> - Ioi
>
>> Also, I realized I did not remove the TraceDefaultMethods flag from 
>> globals.hpp, so here is the link to the updated webrev: 
>> http://cr.openjdk.java.net/~rprotacio/8139564.01/
>> Which builds appropriately. The change now encompasses all the 
>> references to TraceDefaultMethods. A compatibility request has been 
>> accepted with regards to this change.
>>
>> Thanks,
>> Rachel
>>
>> On 10/14/2015 11:58 PM, Ioi Lam wrote:
>>> Hi Rachel,
>>>
>>> Before your changes, this block of code  would be excluded from 
>>> product builds:
>>>
>>>  684 #ifndef PRODUCT
>>>  685   if (TraceDefaultMethods) {
>>>  686     tty->print_cr("Slots that need filling:");
>>>  687     streamIndentor si(tty);
>>>  688     for (int i = 0; i < slots->length(); ++i) {
>>>  689       tty->indent();
>>>  690       slots->at(i)->print_on(tty);
>>>  691       tty->cr();
>>>  692     }
>>>  693   }
>>>  694 #endif // ndef PRODUCT
>>>
>>> but after your change, it will be included in product builds. This 
>>> means product builds will have more verbose output than before. It 
>>> also means that the product builds will get bigger (because some 
>>> printing code, such as EmptyVtableSlot::print_on(), would need to be 
>>> enabled for product builds as well).
>>>
>>> I am not very familiar with UL so maybe this is an FAQ ... while 
>>> doing the UL conversion, should we add all the old "ifndef PRODUCT" 
>>> logs into the product build?
>>>
>>> Thanks
>>> - Ioi
>>>
>>> On 10/14/15 7:10 PM, Rachel Protacio wrote:
>>>> Hello! Please take a look at my enhancement, the first of the 
>>>> runtime logging flags to be converted.
>>>>
>>>> Summary: The former -XX:+TraceDefaultMethods flag is updated to the 
>>>> unified logging framework and is now replaced with 
>>>> -Xlog:defaultmethods.
>>>>
>>>> open webrev: http://cr.openjdk.java.net/~rprotacio/8139564/
>>>> bug: https://bugs.openjdk.java.net/browse/JDK-8139564
>>>> testing: Passes JPRT, RBT, and RefWorkload performance testing.
>>>>
>>>> Thank you,
>>>> Rachel
>>>
>>
>