Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

racle.com> Cc: hotspot-...@openjdk.java.net; core-libs-dev Subject: Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections Goetz, The reserved zone is sometime considered as a subpart of the yellow zone, and sometime as an independent entity. Technically the reserved zone is plac

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Karen, Thank you for your review. Fred On 23/11/2015 20:10, Karen Kinnear wrote: Frederic, Looks good. Many thanks. Karen On Nov 23, 2015, at 12:44 PM, Frederic Parain > wrote: Karen, Thank you for your review, my answers

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

aren Kinnear <karen.kinn...@oracle.com> Cc: hotspot-...@openjdk.java.net; core-libs-dev Subject: Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections Karen, Thank you for your review. Fred On 23/11/2015 20:10, Karen Kinnear wrote: Frederic, Looks good. Many

RE: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

v-boun...@openjdk.java.net] On > Behalf Of Frederic Parain > Sent: Montag, 14. Dezember 2015 14:24 > To: Karen Kinnear <karen.kinn...@oracle.com> > Cc: hotspot-...@openjdk.java.net; core-libs-dev d...@openjdk.java.net> > Subject: Re: RFR(L): JDK-8046936 : JEP 270: Reser

RE: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

; Karen Kinnear > <karen.kinn...@oracle.com> > Cc: hotspot-...@openjdk.java.net; core-libs-dev d...@openjdk.java.net> > Subject: Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical > Sections > > Goetz, > > The reserved zone is sometime considered as a subpart o

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 6/12/2015 2:23 AM, Doug Lea wrote: On 12/03/2015 12:53 AM, David Holmes wrote: On 3/12/2015 12:56 AM, Doug Lea wrote: In the absence of any of: tail-recursion support, reliable cleanup, or growable stacks, it seems reasonable to choose larger default stack sizes so that these long but

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 12/03/2015 12:53 AM, David Holmes wrote: On 3/12/2015 12:56 AM, Doug Lea wrote: In the absence of any of: tail-recursion support, reliable cleanup, or growable stacks, it seems reasonable to choose larger default stack sizes so that these long but finite chains of completions are far less

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

All fixed. Thank you Dan. Fred On 02/12/2015 19:22, Daniel D. Daugherty wrote: On 12/1/15 9:21 AM, Frederic Parain wrote: Hi Dan, Thank you for your detailed review. My answers are in-lined below. New webrev: http://cr.openjdk.java.net/~fparain/8046936/webrev.02/hotspot/ Re-reviewed by

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Bringing Martin's JEP comment (https://bugs.openjdk.java.net/browse/JDK-8046936) to the lists: Approximately 100% of the cases of StackOverflowError (SOE) we hear about lately on concurrency-interest are due to long chains of CompletableFutures that exist because of the lack of tail-recursion

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 12/02/2015 02:56 PM, Doug Lea wrote: > On 32bit systems the 1MB limit is completely defensible. But expanding > to say 64MB on 64bit systems would reduce practical encounters with > SOE in these kinds of constructions by a factor of 64 or so. > Is there any reason not to do this? Some cloud

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 12/1/15 9:21 AM, Frederic Parain wrote: Hi Dan, Thank you for your detailed review. My answers are in-lined below. New webrev: http://cr.openjdk.java.net/~fparain/8046936/webrev.02/hotspot/ Re-reviewed by comparing 8046936.0[12].hotspot.patch in jfilemerge... Just a couple of nits:

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 3/12/2015 12:56 AM, Doug Lea wrote: Bringing Martin's JEP comment (https://bugs.openjdk.java.net/browse/JDK-8046936) to the lists: Approximately 100% of the cases of StackOverflowError (SOE) we hear about lately on concurrency-interest are due to long chains of CompletableFutures that exist

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Hi Dan, Thank you for your detailed review. My answers are in-lined below. New webrev: http://cr.openjdk.java.net/~fparain/8046936/webrev.02/hotspot/ On 24/11/2015 17:26, Daniel D. Daugherty wrote: src/cpu/sparc/vm/frame_sparc.cpp (old) L635: if (fp() - sp() > 1024 +

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 11/23/15 10:44 AM, Frederic Parain wrote: Karen, Thank you for your review, my answers are in-lined below. New Webrevs (including some fixes suggested by Paul Sandoz): http://cr.openjdk.java.net/~fparain/8046936/webrev.01/hotspot/ src/cpu/sparc/vm/frame_sparc.cpp (old) L635: if

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On Nov 24, 2015, at 8:46 AM, Karen Kinnear wrote: > Doug, > > I have been thinking about this more from the perspective of the original > problem > we set out to solve I apologize if this has already been considered -- but for a lot well designed systems,

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Doug, I have been thinking about this more from the perspective of the original problem we set out to solve, which was identified in the concurrent hash map usage, at the time in the class loading logic. While the class loading logic has changed, I think we have enough experience with this

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Karen, Thank you for your review, my answers are in-lined below. New Webrevs (including some fixes suggested by Paul Sandoz): http://cr.openjdk.java.net/~fparain/8046936/webrev.01/hotspot/ http://cr.openjdk.java.net/~fparain/8046936/webrev.01/jdk/ On 20/11/2015 19:44, Karen Kinnear wrote:

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Frederic, Looks good. Many thanks. Karen > On Nov 23, 2015, at 12:44 PM, Frederic Parain > wrote: > > Karen, > > Thank you for your review, my answers are in-lined below. > > New Webrevs (including some fixes suggested by Paul Sandoz): > >

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 11/20/2015 12:40 PM, Karen Kinnear wrote: Totally appreciate the suggestion that the java.util.concurrent modifications be done by folks with more domain expertise. Would you have us incorporate the initial minimal set of j.u.c. updates or none at all? Sorry that I'm still in foot-drag

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

One other example is an unlock that requires three steps - update state, update owner and unpark successor. thanks, Karen > On Nov 19, 2015, at 9:25 PM, David Holmes wrote: > > On 20/11/2015 4:10 AM, Doug Lea wrote: >> On 11/16/2015 08:00 PM, David Holmes wrote:

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Totally appreciate the suggestion that the java.util.concurrent modifications be done by folks with more domain expertise. Would you have us incorporate the initial minimal set of j.u.c. updates or none at all? thanks, Karen > On Nov 11, 2015, at 8:09 PM, Doug Lea wrote: >

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Frederic, Code review for web revs you sent out. Code looks good. I am not as familiar with the compiler code. I realize you need to check in at least a subset of the java.util.concurrent changes for the test to work, so maybe I should not have asked Doug about his preference there. Sorry. I

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 11/16/2015 08:00 PM, David Holmes wrote: I've tried that :-) The amount of code being executed with the ReservedStackAccess privilege tends to increase very quickly and I was concerned about keeping the size of the reserved area small. How much space does each level of calling need? I know

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 20/11/2015 4:10 AM, Doug Lea wrote: On 11/16/2015 08:00 PM, David Holmes wrote: I've tried that :-) The amount of code being executed with the ReservedStackAccess privilege tends to increase very quickly and I was concerned about keeping the size of the reserved area small. How much space

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Hi Fred, On 11/11/2015 3:38 AM, frederic parain wrote: Hi David and Doug, Thank you for your feedback. I put some comments below. On 09/11/2015 08:12, David Holmes wrote: Hi Doug, On 9/11/2015 9:31 AM, Doug Lea wrote: On 11/06/2015 02:23 AM, David Holmes wrote: Before I look at the

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 11/10/2015 12:38 PM, frederic parain wrote: If I put on some extra-strength rose-coloured glasses I think I can almost read that as "something is better than nothing". ;-) Yeah, that's what I meant :-) It is good to at least have the @ReservedStackAccess annotation and mechanism in place.

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Hi David and Doug, Thank you for your feedback. I put some comments below. On 09/11/2015 08:12, David Holmes wrote: Hi Doug, On 9/11/2015 9:31 AM, Doug Lea wrote: On 11/06/2015 02:23 AM, David Holmes wrote: Before I look at the code, what is the status of the "Open Issues" referenced in

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

On 11/06/2015 02:23 AM, David Holmes wrote: Before I look at the code, what is the status of the "Open Issues" referenced in the JEP? Also the JDK changes need to be reviewed on core-libs-dev and in particular must be seen by the jsr166 maintainers (ie Doug Lea and Martin Buchholz) Martin

Re: RFR(L): JDK-8046936 : JEP 270: Reserved Stack Areas for Critical Sections

Hi Doug, On 9/11/2015 9:31 AM, Doug Lea wrote: On 11/06/2015 02:23 AM, David Holmes wrote: Before I look at the code, what is the status of the "Open Issues" referenced in the JEP? Also the JDK changes need to be reviewed on core-libs-dev and in particular must be seen by the jsr166