RFR: 8216303: JFR: Simplify generated files

[Erik Gahlin]

Thanks for the reviews.

Erik

> On 28 May 2020, at 22:55, Erik Joelsson <erik.joelsson at oracle.com> wrote:
> 
> 
> On 2020-05-28 13:51, Erik Gahlin wrote:
>> Hello Erik,
>> 
>>> On 28 May 2020, at 19:47, Erik Joelsson <erik.joelsson at oracle.com> wrote:
>>> 
>>> Hello Erik,
>>> 
>>> I noticed that you added an import for java.util.HashSet, but it doesn't seem to be used.
>> Fixed.
>> 
>>> You also replaced the only use of HashMap with LinkedHashMap, which we like as it gives a predictable iteration order, but forgot to remove the import.
>>> 
>>> Do you know if the generated files are stable over several builds?
>> They should be stable. Events are numbered after how they are specified in /hotspot/share/jfr/metadata/metadata.xml.
> 
> Good thanks! Then I'm happy with this.
> 
> /Erik
> 
>> Erik
>> 
>>> /Erik
>>> 
>>> On 2020-05-28 10:37, Erik Gahlin wrote:
>>>> Hi,
>>>> 
>>>> Could I have a review of a fix that removes legacy in the generated JFR event files, in particular hard coded numbers for type / event IDs. Event IDs are now numbered from zero, which has the benefit that most of them can be represented as a single byte instead of two. This will reduce the size of recordings with a few percent.
>>>> 
>>>> I’m looping in build-dev, since I am modifying make/src/classes/build/tools/jfr/GenerateJfrFiles.java, but there are no changes to how things are built. The generated JFR files are just slightly different.
>>>> 
>>>> Old and new files:
>>>> http://cr.openjdk.java.net/~egahlin/8216303_generated/
>>>> 
>>>> Bug:
>>>> https://bugs.openjdk.java.net/browse/JDK-8216303
>>>> 
>>>> Webrev:
>>>> http://cr.openjdk.java.net/~egahlin/8216303/
>>>> 
>>>> Testing:
>>>> - Building with and without jfr the feature enabled
>>>> - Tier 1/2 (Mac, Linux and Windows)
>>>> - JFR tests in test/jdk/jdk/jfr
>>>> 
>>>> Thanks
>>>> Erik
>>>> 
>>>>