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<a class="moz-txt-link-freetext"
href="https://bugs.openjdk.java.net/browse/JDK-8149343">https://bugs.openjdk.java.net/browse/JDK-8149343</a><br>
<br>
The error here was that the number of active workers was<br>
not always set correctly for parallel Reference processing.<br>
The first fix was to set the number of active workers in the<br>
ReferenceProcessor in the task constructor. Once that<a
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was fixed a subsequent assertion failure occurred.<br>
<br>
# Internal Error
(/export/jmasa/java/jdk9-rt-8149343/src/share/vm/gc/shared/referenceProcessor.cpp:884),
pid=18444, tid=18500<br>
# assert(id < _max_num_q) failed: Id is out-of-bounds id 23 and
max id 23)<br>
<br>
This was fixed by the change<span class="removed"><br>
<br>
- if (++_next_id == _num_q) {<br>
+ assert(!_discovery_is_mt, "Round robin should only be used in
serial discovery");<br>
+ if (++_next_id >= _num_q) {<br>
<br>
</span>See the CR for an example log which showed _num_q changing<br>
values between different phases of a collection and where the<br>
value of _next_id was greater than _num_q.<br>
<br>
The last change was to add a parameter to the logging function so
that<br>
the logging only output the active lists (which made the reading of
the<br>
logs simpler)<br>
<br>
- void log_reflist_counts(DiscoveredList ref_lists[], size_t
total_count) PRODUCT_RETURN;<br>
+ void log_reflist_counts(DiscoveredList ref_lists[], uint
active_length, size_t total_count) PRODUCT_RETURN;<br>
<br>
This patch fixes UseG1GC for the failure where <br>
UseDynamicNumberOfGCThreads and <span class="new">ParallelRefProcEnabled<br>
are both turned on. There is still a failure with UseParallelGC<br>
that is being fixed under 8150994.<br>
</span> <br>
<a class="moz-txt-link-freetext"
href="http://cr.openjdk.java.net/%7Ejmasa/8149343/webrev.00/">http://cr.openjdk.java.net/~jmasa/8149343/webrev.00/</a><br>
<br>
Testing: gc_test_suite with UseDynamicNumberOfGCThreads on and<br>
ParallelRefProcEnabled on and off. rbt in progress<br>
<br>
Thanks.<br>
<br>
Jon<br>
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