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List: openjdk-serviceability-dev
Subject: Re: RFR (M): 8207266: ThreadMXBean::getThreadAllocatedBytes() can be quicker for self thread
From: Mandy Chung <mandy.chung () oracle ! com>
Date: 2019-08-30 23:25:30
Message-ID: 0d42d653-d158-a6e4-45b6-84f087c7e592 () oracle ! com
[Download RAW message or body]
CSR reviewed.
management.cpp
2083 java_thread = (JavaThread*)THREAD;
2084 if (java_thread->is_Java_thread()) {
2085 return java_thread->cooked_allocated_bytes();
2086 }
The cast should be done after is_Java_thread() test.
ThreadImpl.java
162 private void throwIfNullThreadIds(long[] ids) {
Even better: simply use Objects::requiresNonNull and this method can be
removed.
This suggests positive naming alternative to
throwIfThreadAllocatedMemoryNotSupported -
"ensureThreadAllocatedMemorySupported" (sorry I should have suggested that)
ThreadMXBean.java
130 * @throws java.lang.UnsupportedOperationException if the Java
virtual
Nit: "java.lang." can be dropped.
@since 14 is missing.
Mandy
On 8/30/19 3:33 PM, Hohensee, Paul wrote:
>
> Thanks for your review, Mandy. Revised webrev at
> http://cr.openjdk.java.net/~phh/8207266/webrev.02/.
>
> I updated the CSR with your suggested javadoc for
> getCurrentThreadAllocatedBytes. It now matches that for
> getCurrentThreadUserTime and getCurrentThreadCputime. I also fixed the
> "convenient" -> "convenience" typos in j.l.m.ThreadMXBean.java.
>
> I meant GetOneThreads to be the possessive, but don't feel strongly
> either way so I'm fine with GetOneThread.
>
> I updated ThreadImpl.java as you suggested, though in
> getThreadAllocatedBytes(long[] ids) I had to add a
> redundant-in-the-not-length-1-case check for a null ids reference.
> Would someone take a look at the Hotspot side and the test please?
> Paul
>
> *From: *Mandy Chung <mandy.chung@oracle.com>
> *Date: *Friday, August 30, 2019 at 10:22 AM
> *To: *"Hohensee, Paul" <hohensee@amazon.com>
> *Cc: *OpenJDK Serviceability <serviceability-dev@openjdk.java.net>,
> "hotspot-gc-dev@openjdk.java.net" <hotspot-gc-dev@openjdk.java.net>
> *Subject: *Re: RFR (M): 8207266:
> ThreadMXBean::getThreadAllocatedBytes() can be quicker for self thread
>
> OK. That's better. Some review comments:
>
> The javadoc of getCurrentThreadAllocatedBytes() can simply say:
>
> "Returns an approximation of the total amount of memory, in bytes,
> allocated in heap memory for the current thread.
>
> This is a convenient method for local management use and is equivalent
> to calling getThreadAllocatedBytes(Thread.currentThread().getId()).
>
>
> src/hotspot/share/include/jmm.h
>
> GetOneThreadsAllocatedMemory: s/OneThreads/OneThread/
>
> sun/management/ThreadImpl.java
>
> 43 private static final String
> THREAD_ALLOCATED_MEMORY_NOT_SUPPORTED =
> 44 "Thread allocated memory measurement is not supported.";
>
> if (!isThreadAllocatedMemorySupported()) {
> throw new
> UnsupportedOperationException(THREAD_ALLOCATED_MEMORY_NOT_SUPPORTED);
> }
>
> Perhaps the above can be refactored as
> throwIfAllocatedMemoryUnsupported() method.
>
> 391 if (ids.length == 1) {
> 392 sizes[0] = -1;
> :
> 398 if (ids.length == 1) {
> 399 long id = ids[0];
> 400 sizes[0] = getThreadAllocatedMemory0(
> 401 Thread.currentThread().getId() == id ? 0 : id);
> 402 } else {
>
> It seems cleaner to handle the 1-element array case at the beginning
> of this method:
> if (ids.length == 1) {
> long size = getThreadAllocatedBytes(ids[0]);
> return new long[] { size };
> }
>
> I didn't review the hotspot implementation and the test.
>
> Mandy
>
> On 8/29/19 10:01 AM, Hohensee, Paul wrote:
>
> My bad, Mandy. The webrev puts getCurrentThreadAllocatedBytes in
> com.sun.management.ThreadMXBean along with the current two
> getThreadAllocatedBytes methods for the reasons you list. I've
> updated the CSR to specify com.sun.management and added a
> rationale. AllocatedBytes is currently enabled by Hotspot by
> default because the overhead of recording TLAB occupancy is
> negligible.
>
> There's no new GC code, nor will there be, so imo we don't have to
> involve the GC folks. I.e., the new JMM method
> GetOneThreadsAllocatedBytes uses the existing
> cooked_allocated_bytes JavaThread method, and
> getCurrentThreadAllocatedBytes is the same as
> getThreadAllocatedBytes: it just bypasses the thread lookup code.
>
> I hadn't tracked down what happens when getCurrentThreadUserTime
> and getCurrentThreadCpuTime are called before, but if I'm not
> mistaken, it the code in jcmd() in attachListener.cpp will call
> GetThreadCpuTimeWithKind in management.cpp, and it will ultimately
> use Thread::current() as the subject of the call, see
> os::current_thread_cpu_time in os_linux.cpp. That means that the
> CurrentThread methods should work remotely the same way they do
> locally. GetOneThreadsAllocatedBytes in management.cpp uses THREAD
> as its subject when called on behalf of
> getCurrentThreadAllocatedBytes, so it will also uses the current
> remote Java thread. Even if these methods only worked locally,
> there are many setups where apps are self-monitoring that could
> use the performance improvement.
>
> Thanks,
>
> Paul
>
> *From: *Mandy Chung <mandy.chung@oracle.com>
> <mailto:mandy.chung@oracle.com>
> *Date: *Wednesday, August 28, 2019 at 3:59 PM
> *To: *"Hohensee, Paul" <hohensee@amazon.com>
> <mailto:hohensee@amazon.com>
> *Cc: *OpenJDK Serviceability <serviceability-dev@openjdk.java.net>
> <mailto:serviceability-dev@openjdk.java.net>,
> "hotspot-gc-dev@openjdk.java.net"
> <mailto:hotspot-gc-dev@openjdk.java.net>
> <hotspot-gc-dev@openjdk.java.net>
> <mailto:hotspot-gc-dev@openjdk.java.net>
> *Subject: *Re: RFR (M): 8207266:
> ThreadMXBean::getThreadAllocatedBytes() can be quicker for self thread
>
> Hi Paul,
>
> The CSR proposes this method in java.lang.management.ThreadMXBean
> as a Java SE feature.
>
> Has this been discussed with the GC team to commit measuring
> current thread's allocated bytes as Java SE feature? Can this be
> supported by all JVM implementation? What is the overhead if
> this is enabled by default? Does it need to be disabled? This
> metric is from TLAB that might be okay. This needs
> advice/discussion with GC experts.
>
> I see that CSR mentions it can be disabled and link to
> isThreadAllocatedMemoryEnabled() and
> setThreadAllocatedMemoryEnabled() methods but these methods are
> defined in com.sun.management.ThreadMXBean.
>
> As Alan points out, current thread makes sense only in local VM
> management. When this is monitored from a JMX client (e.g.
> jconsole to connect to a running JVM,
> "currentThreadAllowcatedBytes" attribute is the current thread in
> jconsole process which invoking Thread::currentThread?
>
> Mandy
>
> On 8/28/19 12:22 PM, Hohensee, Paul wrote:
>
> Please review a performance improvement for
> ThreadMXBean.getThreadAllocatedBytes and the addition of
> getCurrentThreadAllocatedBytes.
>
> JBS issue:https://bugs.openjdk.java.net/browse/JDK-8207266
>
> Webrev:http://cr.openjdk.java.net/~phh/8207266/webrev.00/
>
> CSR:https://bugs.openjdk.java.net/browse/JDK-8230311
>
> Previous email threads:
> https://mail.openjdk.java.net/pipermail/serviceability-dev/2018-July/024441.html
> https://mail.openjdk.java.net/pipermail/serviceability-dev/2018-August/024763.html
>
> The CSR is for adding
> ThreadMXBean.getCurrentThreadAllocatedBytes. I'd be great for
> someone to review it.
>
> I took Mandy's advice and put the fast paths in the library
> code. I added a new JMM method GetOneThreadsAllocatedBytes
> that works the same as GetThreadCpuTime: it uses a thread_id
> value of zero to distinguish the current thread. On my Mac
> laptop, the result runs 47x faster for the current thread than
> the old implementation.
>
> The 3 tests intest/jdk/com/sun/management/ThreadMXBean all
> pass. I added code to ThreadAllocatedMemory.java to test
> getCurrentThreadAllocatedBytes as well as variations on
> getThreadAllocatedBytes(id). A submit repo job is in progress.
>
> Thanks,
>
> Paul
>
>
>
>
>
>
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CSR reviewed.<br>
<br>
management.cpp<br>
2083 java_thread = (JavaThread*)THREAD;<br>
2084 if (java_thread->is_Java_thread()) {<br>
2085 return java_thread->cooked_allocated_bytes();<br>
2086 }<br>
<br>
The cast should be done after is_Java_thread() test.<br>
<br>
ThreadImpl.java<br>
162 private void throwIfNullThreadIds(long[] ids) {<br>
<br>
Even better: simply use Objects::requiresNonNull and this method can
be removed.<br>
<br>
This suggests positive naming alternative to
throwIfThreadAllocatedMemoryNotSupported -
"ensureThreadAllocatedMemorySupported" (sorry I should have
suggested that)<br>
<br>
ThreadMXBean.java<br>
130 * @throws java.lang.UnsupportedOperationException if the
Java virtual<br>
<br>
Nit: "java.lang." can be dropped.<br>
<br>
@since 14 is missing.<br>
<br>
Mandy<br>
<br>
<div class="moz-cite-prefix">On 8/30/19 3:33 PM, Hohensee, Paul
wrote:<br>
</div>
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<p class="MsoNormal"><span style="font-size:11.0pt">Thanks for
your review, Mandy. Revised webrev at
<a class="moz-txt-link-freetext" \
href="http://cr.openjdk.java.net/~phh/8207266/webrev.02/">http://cr.openjdk.java.net/~phh/8207266/webrev.02/</a>.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I updated
the CSR with your suggested javadoc for
getCurrentThreadAllocatedBytes. It now matches that for
getCurrentThreadUserTime and getCurrentThreadCputime. I also
fixed the "convenient" -> "convenience" typos in
j.l.m.ThreadMXBean.java.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I meant
GetOneThreads to be the possessive, but don't feel strongly
either way so I'm fine with GetOneThread.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<pre><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">I \
updated ThreadImpl.java as you suggested, though </span><span \
style="font-size:11.0pt;font-family:"Calibri",sans-serif">in \
getThreadAllocatedBytes(long[] ids) I had to add a redundant-in-the-not-length-1-case \
check for a null ids reference.<o:p></o:p></span></pre>
<pre><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> \
</o:p></span></pre> <pre><span \
style="font-size:11.0pt;font-family:"Calibri",sans-serif">Would someone \
take a look at the Hotspot side and the test \
please?<o:p></o:p></span></pre>
<pre><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> \
</o:p></span></pre>
<pre><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Paul<o:p></o:p></span></pre>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<div style="border:none;border-top:solid #B5C4DF
1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b><span style="color:black">From: </span></b><span
style="color:black">Mandy Chung
<a class="moz-txt-link-rfc2396E" \
href="mailto:mandy.chung@oracle.com"><mandy.chung@oracle.com></a><br> <b>Date: \
</b>Friday, August 30, 2019 at 10:22 AM<br>
<b>To: </b>"Hohensee, Paul" <a class="moz-txt-link-rfc2396E" \
href="mailto:hohensee@amazon.com"><hohensee@amazon.com></a><br> <b>Cc: \
</b>OpenJDK Serviceability
<a class="moz-txt-link-rfc2396E" \
href="mailto:serviceability-dev@openjdk.java.net"><serviceability-dev@openjdk.java.net></a>,
<a class="moz-txt-link-rfc2396E" \
href="mailto:hotspot-gc-dev@openjdk.java.net">"hotspot-gc-dev@openjdk.java.net"</a>
<a class="moz-txt-link-rfc2396E" \
href="mailto:hotspot-gc-dev@openjdk.java.net"><hotspot-gc-dev@openjdk.java.net></a><br>
<b>Subject: </b>Re: RFR (M): 8207266:
ThreadMXBean::getThreadAllocatedBytes() can be quicker for
self thread<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> \
</o:p></span></p> </div>
<p class="MsoNormal" style="margin-bottom:12.0pt"><tt><span
style="font-size:10.0pt">OK. That's better. Some review
comments:</span></tt><span
style="font-size:10.0pt;font-family:"Courier New""><br>
<br>
<tt>The javadoc of getCurrentThreadAllocatedBytes() can
simply say:</tt><br>
<br>
<tt>"Returns an approximation of the total amount of memory,
in bytes,</tt><br>
<tt>allocated in heap memory for the current thread.</tt><br>
<br>
<tt>This is a convenient method for local management use and
is equivalent</tt><br>
<tt>to calling
getThreadAllocatedBytes(Thread.currentThread().getId()).
</tt><br>
<br>
<br>
</span>src/hotspot/share/include/jmm.h<br>
<br>
<tt><span style="font-size:10.0pt">GetOneThreadsAllocatedMemory:
s/OneThreads/OneThread/</span></tt><span
style="font-size:10.0pt;font-family:"Courier New""><br>
<br>
<tt>sun/management/ThreadImpl.java</tt><br>
<br>
<tt> 43 private static final String
THREAD_ALLOCATED_MEMORY_NOT_SUPPORTED =</tt><br>
<tt> 44 "Thread allocated memory measurement is not
supported.";</tt><br>
<br>
<tt>if (!isThreadAllocatedMemorySupported()) {</tt><br>
<tt> throw new
UnsupportedOperationException(THREAD_ALLOCATED_MEMORY_NOT_SUPPORTED);</tt><br>
<tt>}</tt><br>
<br>
<tt>Perhaps the above can be refactored as
throwIfAllocatedMemoryUnsupported() method.</tt><br>
<tt> </tt><br>
<tt> 391 if (ids.length == 1) {</tt><br>
<tt> 392 sizes[0] = -1;</tt><br>
<tt> :</tt><br>
<tt> 398 if (ids.length == 1) {</tt><br>
<tt> 399 long id = ids[0];</tt><br>
<tt> 400 sizes[0] =
getThreadAllocatedMemory0(</tt><br>
<tt> 401 \
Thread.currentThread().getId() == id ? 0 : id);</tt><br>
<tt> 402 } else {</tt><br>
<br>
<tt>It seems cleaner to handle the 1-element array case at
the beginning</tt><br>
<tt>of this method:</tt><br>
<tt> if (ids.length == 1) {</tt><br>
<tt> long size = getThreadAllocatedBytes(ids[0]);</tt><br>
<tt> return new long[] { size };</tt><br>
<tt> }</tt><br>
<br>
<tt>I didn't review the hotspot implementation and the test.</tt><br>
<tt> </tt><br>
<tt>Mandy</tt></span><o:p></o:p></p>
<div>
<p class="MsoNormal">On 8/29/19 10:01 AM, Hohensee, Paul
wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt">My bad,
Mandy. The webrev puts getCurrentThreadAllocatedBytes in
com.sun.management.ThreadMXBean along with the current two
getThreadAllocatedBytes methods for the reasons you list.
I've updated the CSR to specify com.sun.management and
added a rationale. AllocatedBytes is currently enabled by
Hotspot by default because the overhead of recording TLAB
occupancy is negligible.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> \
</span><o:p></o:p></p> <p class="MsoNormal"><span style="font-size:11.0pt">There's \
no new GC code, nor will there be, so imo we don't have to
involve the GC folks. I.e., the new JMM method
GetOneThreadsAllocatedBytes uses the existing
cooked_allocated_bytes JavaThread method, and
getCurrentThreadAllocatedBytes is the same as
getThreadAllocatedBytes: it just bypasses the thread
lookup code.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> \
</span><o:p></o:p></p> <p class="MsoNormal"><span style="font-size:11.0pt">I hadn't
tracked down what happens when getCurrentThreadUserTime
and getCurrentThreadCpuTime are called before, but if I'm
not mistaken, it the code in jcmd() in attachListener.cpp
will call GetThreadCpuTimeWithKind in management.cpp, and
it will ultimately use Thread::current() as the subject of
the call, see os::current_thread_cpu_time in os_linux.cpp.
That means that the CurrentThread methods should work
remotely the same way they do locally.
GetOneThreadsAllocatedBytes in management.cpp uses THREAD
as its subject when called on behalf of
getCurrentThreadAllocatedBytes, so it will also uses the
current remote Java thread. Even if these methods only
worked locally, there are many setups where apps are
self-monitoring that could use the performance
improvement.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> \
</span><o:p></o:p></p>
<p class="MsoNormal"><span \
style="font-size:11.0pt">Thanks,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> \
</span><o:p></o:p></p>
<p class="MsoNormal"><span \
style="font-size:11.0pt">Paul</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> \
</span><o:p></o:p></p> <div style="border:none;border-top:solid #B5C4DF
1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b><span style="color:black">From: </span></b><span
style="color:black">Mandy Chung
<a href="mailto:mandy.chung@oracle.com"
moz-do-not-send="true"><mandy.chung@oracle.com></a><br>
<b>Date: </b>Wednesday, August 28, 2019 at 3:59 PM<br>
<b>To: </b>"Hohensee, Paul" <a
href="mailto:hohensee@amazon.com"
moz-do-not-send="true"><hohensee@amazon.com></a><br>
<b>Cc: </b>OpenJDK Serviceability <a
href="mailto:serviceability-dev@openjdk.java.net"
moz-do-not-send="true">
<serviceability-dev@openjdk.java.net></a>, <a
href="mailto:hotspot-gc-dev@openjdk.java.net"
moz-do-not-send="true">
"hotspot-gc-dev@openjdk.java.net"</a> <a
href="mailto:hotspot-gc-dev@openjdk.java.net"
moz-do-not-send="true">
<hotspot-gc-dev@openjdk.java.net></a><br>
<b>Subject: </b>Re: RFR (M): 8207266:
ThreadMXBean::getThreadAllocatedBytes() can be quicker
for self thread</span><o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt"> \
</span><o:p></o:p></p> </div>
<p class="MsoNormal" style="margin-bottom:12.0pt">Hi Paul,<br>
<br>
The CSR proposes this method in
java.lang.management.ThreadMXBean as a Java SE feature.<br>
<br>
Has this been discussed with the GC team to commit measuring
current thread's allocated bytes as Java SE feature? Can
this be supported by all JVM implementation? What is the
overhead if this is enabled by default? Does it need to be
disabled? This metric is from TLAB that might be okay.
This needs advice/discussion with GC experts.<br>
<br>
I see that CSR mentions it can be disabled and link to
isThreadAllocatedMemoryEnabled() and
setThreadAllocatedMemoryEnabled() methods but these methods
are defined in com.sun.management.ThreadMXBean.
<br>
<br>
As Alan points out, current thread makes sense only in local
VM management. When this is monitored from a JMX client
(e.g. jconsole to connect to a running JVM,
"currentThreadAllowcatedBytes" attribute is the current
thread in jconsole process which invoking
Thread::currentThread?<br>
<br>
Mandy<o:p></o:p></p>
<div>
<p class="MsoNormal">On 8/28/19 12:22 PM, Hohensee, Paul
wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span style="color:black">Please review
a performance improvement for
ThreadMXBean.getThreadAllocatedBytes and the addition of
getCurrentThreadAllocatedBytes.</span><o:p></o:p></p>
<p class="MsoNormal" style="caret-color: rgb(0, 0,
0);font-variant-caps: normal;orphans:
auto;text-align:start;widows:
auto;-webkit-text-size-adjust:
auto;-webkit-text-stroke-width: 0px;word-spacing:0px">
<span style="color:black"> </span><o:p></o:p></p>
<p class="MsoNormal" style="caret-color: rgb(0, 0,
0);font-variant-caps: normal;orphans:
auto;text-align:start;widows:
auto;-webkit-text-size-adjust:
auto;-webkit-text-stroke-width: 0px;word-spacing:0px">
<span style="color:black">JBS issue:<span
class="apple-converted-space"> </span></span><a
href="https://bugs.openjdk.java.net/browse/JDK-8207266"
title="https://bugs.openjdk.java.net/browse/JDK-8207266"
moz-do-not-send="true"><span \
style="color:#954F72">https://bugs.openjdk.java.net/browse/JDK-8207266</span></a><o:p></o:p></p>
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<span style="color:black">Webrev:<span
class="apple-converted-space"> </span></span><a
href="http://cr.openjdk.java.net/~phh/8207266/webrev.00/"
title="http://cr.openjdk.java.net/~phh/8207266/webrev.00/"
moz-do-not-send="true"><span \
style="color:#954F72">http://cr.openjdk.java.net/~phh/8207266/webrev.00/</span></a><o:p></o:p></p>
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<span style="color:black">CSR:<span
class="apple-converted-space"> </span></span><a
href="https://bugs.openjdk.java.net/browse/JDK-8230311"
title="https://bugs.openjdk.java.net/browse/JDK-8230311"
moz-do-not-send="true"><span \
style="color:#954F72">https://bugs.openjdk.java.net/browse/JDK-8230311</span></a><o:p></o:p></p>
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<span style="color:black"> </span><o:p></o:p></p>
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<span style="color:black">Previous email threads:<br>
</span><a
href="https://mail.openjdk.java.net/pipermail/serviceability-dev/2018-July/024441.html"
moz-do-not-send="true"><span \
style="color:#954F72">https://mail.openjdk.java.net/pipermail/serviceability-dev/2018-July/024441.html</span></a><span
class="apple-converted-space"><span style="color:black"> \
</span></span><span style="color:black"><br>
</span><a
href="https://mail.openjdk.java.net/pipermail/serviceability-dev/2018-August/024763.html"
title="https://mail.openjdk.java.net/pipermail/serviceability-dev/2018-August/024763.html"
moz-do-not-send="true"><span \
style="color:#954F72">https://mail.openjdk.java.net/pipermail/serviceability-dev/2018-August/024763.html</span></a><o:p></o:p></p>
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<span style="color:black"> </span><o:p></o:p></p>
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<span style="color:black">The CSR is for adding
ThreadMXBean.getCurrentThreadAllocatedBytes. I'd be
great for someone to review it.</span><o:p></o:p></p>
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<span style="color:black"> </span><o:p></o:p></p>
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<span style="color:black">I took Mandy's advice and put
the fast paths in the library code. I added a new JMM
method GetOneThreadsAllocatedBytes that works the same
as GetThreadCpuTime: it uses a thread_id value of zero
to distinguish the current thread. On my Mac laptop, the
result runs 47x faster for the current thread than the
old implementation.</span><o:p></o:p></p>
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<span style="color:black"> </span><o:p></o:p></p>
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<span style="color:black">The 3 tests in<span
class="apple-converted-space"> \
</span>test/jdk/com/sun/management/ThreadMXBean all pass. I added code to \
ThreadAllocatedMemory.java to test getCurrentThreadAllocatedBytes as well as
variations on getThreadAllocatedBytes(id). A submit repo
job is in progress.</span><o:p></o:p></p>
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<span style="color:black"> </span><o:p></o:p></p>
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<span style="color:black">Thanks,</span><o:p></o:p></p>
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<span style="color:black"> </span><o:p></o:p></p>
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<span style="color:black">Paul</span><o:p></o:p></p>
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</span><o:p></o:p></p> </blockquote>
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<br>
<br>
</span><o:p></o:p></p>
</blockquote>
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<br>
<o:p></o:p></span></p>
</div>
</blockquote>
<br>
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