RFR(s): 8144527: NewSizeThreadIncrease would make an overflow

[sangheon]

Hi all,

Can I have reviews for this change to prevent an overflow for 
NewSizeThreadIncrease?

This option is used with non-daemon threads count when calculate new 
size. And as we can't know the thread count at start-up time, this 
overflow can't be checked by argument validation framework. Instead I 
changed related routines to prevent the overflow and when it happens 
desired new size will be previous size. This will affect only for Serial GC.

I added simple test to have 5 threads and then check the log whether we 
had heap expansion or not.

CR: https://bugs.openjdk.java.net/browse/JDK-8144527
Webrev: http://cr.openjdk.java.net/~sangheki/8144527/webrev.00
Testing: JPRT

Thanks,
Sangheon