Working on it. I hope to have something to share in the next couple of weeks.
Jeremy On Wed, Aug 12, 2015 at 4:28 AM, Kees Jan Koster <kjkos...@gmail.com> wrote: > Guys, > > This piqued my interest. Where can I find the draft JEP and the sources > for this, please? > > Kees Jan > > > > On 4 Aug 2015, at 23:22, Jeremy Manson <jeremyman...@google.com> wrote: > > > > Thanks, Staffan. I've been tinkering with a draft JEP, but it has been > going slowly because of other craziness in my life. Some responses: > > > > 1) It was a fair bit of work to do it, mostly because it was the first > time I had tinkered with c2. This was 5 years ago. Most of the work since > then has been dealing with merge conflicts. > > > > 2) I did envision a JVMTI interface. More in the JEP. > > > > 3) We have some internal tests, but obviously, we'd have to figure out > how to externalize them. For native code, it's much easier only to have to > worry about building and running on Linux. Presumably, there's already > code in there for JVMTI. > > > > I'll try to get a JEP going for real, although it might not happen in > the next week or so, because I'm moving next week (+the JVMLS). > > > > Jeremy > > > > On Tue, Aug 4, 2015 at 4:04 AM, Staffan Larsen < > staffan.lar...@oracle.com> wrote: > > Hi, > > > > Sorry for being away for so long. > > > > If memory serves me right then the current AllocObjectInNewTLAB JFR > event was written as a way to quickly get some allocation profiling > information with a minimum of VM changes. It probably also carried over to > Hotspot from JRockit. I agree that we can and should collect better > information than what that event does. > > > > I like the approach of instrumenting the interpreter and compiler to do > the sampling. I had thought it would be a lot of work to do it and was > reluctant to go down that path. If the work is already done and Jeremy has > maintained it for a few years without great problems, I think we should > look at bringing it in. I am not worried about the overhead of a decrement > and a compare in the allocation path, but of course we should benchmark > that. > > > > It wasn’t clear to me from the discussion how (or if) this was being > exposed to end users. Was the proposal to just have the native entry points > in the VM and have these be used by various agents? Would this be part of > JVMTI? > > > > I think a draft JEP would be the logical next step and make it easier > for us all to discuss what exactly the proposal should contain. Also, let’s > not forget the need for tests for the feature. > > > > Thanks, > > /Staffan > > > > > > > > > -- > Kees Jan > > http://java-monitor.com/ > kjkos...@kjkoster.org > +31651838192 > > The secret of success lies in the stability of the goal. -- Benjamin > Disraeli > >
