RFR: 8009723 CMS logs "concurrent mode failure" twice when using (disabling) -XX:-UseCMSCompactAtFullCollection

Kevin Walls kevin.walls at oracle.com
Fri Mar 8 15:39:56 PST 2013


Hi,

This is a review request for a small change:

http://cr.openjdk.java.net/~kevinw/8009723/webrev/

Using CMS and disabling UseCMSCompactAtFullCollection on the command 
line easily produces a double-logging of the "(concurrent mode failure)" 
message.  This was spotted by Erik Helin.

This is like removing a print statement.

The webrev contains a testcase, but I am currently suggesting I commit 
this without the test as:

1) it's fairly trivial: remove a print statement, you don't the see 
output of that print statement.
2) it requires -XX:-UseCMSCompactAtFullCollection which I don't believe 
is commonly used
3) it is a CMS-specific and the current test framework is quite awkward 
to make the test specific (manual work in the java test, or re-exec.  If 
re-execing do we ignore TESTVMOPTS or parse it and add 
UseConcMarkSweepGC?... a few issues there we should solve but this may 
not be the test change that needs that...)

So the test is possible, and useful for verifying it if anybody wants to 
run it right now, but does not seem a necessity and for this small 
change adding to the test harness library to make it more elegant seems 
unnecessary for this minor problem...

Thanks
Kevin



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