RFR: 8139564: Convert TraceDefaultMethods to Unified Logging (original) (raw)

Coleen Phillimore coleen.phillimore at oracle.com
Fri Oct 16 16:21:14 UTC 2015

Hi,

I added the serviceability group so they can comment on this as well.
I think having logging in the PRODUCT build is requested so that we can more easily debug customer problems. That said, we will not enable logging in product if we see any performance problem. Also for some options it's possible that these are strictly internal debugging options and in that case we'll either remove them if they're no longer useful, or make them Develop level options.

Printing default methods seems to be something that might be borderline in the second case, but we've decided to make it product level logging. We could change our minds about this though, so your comments are welcome.

Thanks, Coleen

On 10/15/15 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->printcr("Slots that need filling:"); 687 streamIndentor si(tty); 688 for (int i = 0; i < slots->length(); ++i) { 689 tty->indent(); 690 slots->at(i)->printon(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::printon(), 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

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