RFR: 8203832: JWarmup precompile java hot methods at application startup

[yumin qi]

Hi, David

  Thanks for the information. I will create an Enhancement issue in JBS.
Not aware of this procedure.

Thanks
Yumin

On Thu, Mar 14, 2019 at 5:49 PM David Holmes <david.holmes at oracle.com>
wrote:

> Hi Yumin,
>
> On 15/03/2019 8:57 am, yumin qi wrote:
> > Please review the patch for implementing JEP 8203832:
>
> It seems a bit premature for a RFR at this point given the JEP is still
> a draft. Perhaps a RFC is more appropriate?
>
> You need to create an Enhancement issue in JBS, linked to the JEP, to be
> used to push any changes once the JEP has been targeted, then issue your
> RFC/RFR under that bug id.
>
> Thanks,
> David
> -----
>
> > Bug: https://bugs.openjdk.java.net/browse/JDK-8203832
> > Webrev: http://cr.openjdk.java.net/~minqi/8203832/webrev-01/
> >
> > Summary: This patch implements the first version of JIT warmup to
> > solve the java application peak time CPU contest between JIT compiler
> > threads and regula
> > r application java threads. The CPU contest is avoided by pre-run to
> > collect comilation data and precompile the hot java methods during
> > application startu
> > p based on the pre-run collected data.
> >
> > The main flags (-XX:) used to control are:
> > CompilationWarmUpRecording: used for collecting compilation data.
> > Result stored in a file set by flag CompilationWarmUpLogfile.
> > CompilationWarmUp: use collected data to precompile the methods
> > recorded in above file.
> > CompilationWarmUpExclude: configure a file which contains the names to
> > be excluded for precompile.
> > CompilationWarmUpRecordTime: control the warmup recording time.
> > CompilationWarmUpDeoptTime: time (from start) to deoptimize precomiled
> methods.
> >
> > In this version, the profiled method data is not used at
> > precomilation, it will be addressed in followed bug fix. After the
> > first version integrated, will file bug f
> > or it. Also, it does not work with CDS since the data added to
> > ConstantPool data structure. It also will be addressed in another
> > separate bug followed.
> >
> > Test: Submitted to submit repo and passed all tests.
> > Newly added test suites:  test/hotspot/jtreg/jwarmup include test
> > cases for most of the use cases and issues.
> >
> > Thanks
> > Yumin
> >
>