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linzang wants to merge 1 commit into from
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8252105: parallel heap inspection for ZCollectedHeap #103

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@linzang linzang commented Sep 10, 2020 •
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  • enable parallel heap inspection for ZCollectedHeap
  • preliminary evaluation:
    Time of jmap histo on 8GB heap with ~5GB objects
    • before: 7.103s
    • after : 2.734s (with 4 parallel threads)

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  • JDK-8252105: parallel heap inspection for ZCollectedHeap

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$ git fetch https://git.openjdk.java.net/jdk pull/103/head:pull/103
$ git checkout pull/103

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bridgekeeper bot commented Sep 10, 2020

👋 Welcome back lzang! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

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openjdk bot commented Sep 10, 2020

@linzang The following label will be automatically applied to this pull request: hotspot-gc.

When this pull request is ready to be reviewed, an RFR email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label (add|remove) "label" command.

@openjdk openjdk bot added the hotspot-gc hotspot-gc-dev@openjdk.org label Sep 10, 2020
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linzang commented Sep 10, 2020

/label add serviceability

@openjdk openjdk bot added rfr Pull request is ready for review serviceability serviceability-dev@openjdk.org labels Sep 10, 2020
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The serviceability label was successfully added.

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mlbridge bot commented Sep 10, 2020 •
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pliden
pliden reviewed Sep 10, 2020
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Just looked at this briefly. My initial comment is that we need to avoid all the code duplicated from ZHeapIterator and isolate all this a bit better. Perhaps folding everything into one iterator, that can be used by both object_iterate() and parallel_object_iterator(). I'll take a closer look, and perhaps try some alternatives, when I get a chance.

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linzang commented Sep 10, 2020

Hi @pliden,
Thanks for your comments, I will try to merge ZHeapIterator and ZHeapParIterator and update the pr then.
-Lin

@linzang
8252105: parallel heap inspection for ZCollectedHeap
a9b616a 
- enable parallel heap inspection for ZCollectedHeap
- preliminary evaluation:
  Time of jmap histo on 8GB heap with ~5GB objects
  * before: 7.103s
  * after : 2.734s (with 4 parallel threads)
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linzang commented Sep 11, 2020

Hi @pliden,
I updated the PR which merge the changed code into ZHeapIterator.
May I ask your help to review it ? Thanks.
-Lin

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pliden commented Oct 2, 2020

Hi @linzang,

I started reviewing your patch in more detail. However, I ended up with a large number of major comments and I started to feel that it would probably be more productive to create an alternative patch for this, so I did.

master...pliden:8252105_parallel_object_iterator

Some of the main differences compared to your proposed patch:

  • Root scanning is also now done in parallel
  • Same code paths regardless of number of worker threads used
  • Arrays are chunked for better work stealing/balance
  • A terminator is used for better work stealing/balance
  • All of the functionality is isolated (as much as possible) to ZHeapIterator

I think the easiest way forward is probably if you close this PR, and I'll open a new one.

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linzang commented Oct 5, 2020

Hi @pliden,
Sorry for late reply.
I will close this PR and let's discuss in your new one.

-Lin

@linzang linzang closed this Oct 5, 2020
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pliden commented Oct 5, 2020

@linzang Ok, thanks. I created #507.

@linzang linzang deleted the z-par branch November 23, 2021 01:53
pfirmstone pushed a commit to pfirmstone/jdk-with-authorization that referenced this pull request Nov 18, 2024
Serialization - future direction and support for other serialization …
b261b31 
…protocols, via a public Serialization API and JERI Serialization Layer. openjdk#103
pfirmstone pushed a commit to pfirmstone/jdk-with-authorization that referenced this pull request Nov 18, 2024
Serialization - future direction and support for other serialization …
a2f3b4c 
…protocols, via a public Serialization API and JERI Serialization Layer. openjdk#103
pfirmstone pushed a commit to pfirmstone/jdk-with-authorization that referenced this pull request Nov 18, 2024
Serialization - future direction and support for other serialization …
f2662bc 
…protocols, via a public Serialization API and JERI Serialization Layer. openjdk#103

Add Replace interface to allow similar functionality to Java Serialization's writeReplace method.
pfirmstone pushed a commit to pfirmstone/jdk-with-authorization that referenced this pull request Nov 18, 2024
Serialization - future direction and support for other serialization …
ef8ab1e 
…protocols, via a public Serialization API and JERI Serialization Layer. openjdk#103

Implement Replace interface for URICodeSource

PreferredClassProvider creating ClassLoader using proxy codebase URL ProtectionDomain openjdk#125

Add AccessControlContext parameter to constructor, to allow context to be passed in.
pfirmstone pushed a commit to pfirmstone/jdk-with-authorization that referenced this pull request Nov 18, 2024
Serialization - future direction and support for other serialization …
211eadc 
…protocols, via a public Serialization API and JERI Serialization Layer. openjdk#103
pfirmstone pushed a commit to pfirmstone/jdk-with-authorization that referenced this pull request Nov 18, 2024
Serialization - future direction and support for other serialization …
c88b31b 
…protocols, via a public Serialization API and JERI Serialization Layer. openjdk#103
@lfoltan lfoltan mentioned this pull request May 21, 2025
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