Broken thread scheduling in indexed loop (missing safepoint?)

[Alexey Goncharuk]

Hi,

We faced some weird issue with thread scheduling. At a first glance it
looked like it relates to
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7160161 but not exactly.

This is the code we ran:

public static void main(String[] args) throws Exception { Thread worker =
new Thread() { @Override public void run() { double d = 0; for (int j = 1;
j < 2000000000; j++) d += Math.log(Math.E * j); System.out.println(d); } };
Thread reporter = new Thread() { @Override public void run() { try { while
(true) { Thread.sleep(1000); System.out.println("Running: " +
System.currentTimeMillis()); } } catch (InterruptedException ignored) {
Thread.currentThread().interrupt(); } } }; reporter.start();
worker.start(); worker.join(); reporter.interrupt(); }

One can expect that printing thread would output messages during all the
calculation time, however it hangs after 3-4 iterations. Setting
-XX:FreqInlineSize=0
as described in original bug report does not help in this case, but if I
extract loop body into a separate method, setting this option works.
Example passes with -Xint option as well. (Tested with 1.6.0_33, 1.6.0_37,
1.7.0_07 on Windows and 1.6.0_33 on Linux)

I saw #7160161 marked as resolved, so I just wanted to confirm if behavior
we see really relates to this issue and it was fixed (bug report covers
non-Counted loop only).

Also, is there any other workarounds rather then extracting the method and
specifying FreqInlineSize=0?

Thanks,
Alexey Goncharuk
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