Currently, make run-test set concurrency level as the number of CPU divided by 2. This seems to work ok for x64 hardware but less so for Sparc where strands/threads are 8 per cpu core instead of 2 for hyperthreading.
JDK-8230156Adjust default concurrency settings for running tests on Sparc
JDK-8231890Adjust default concurrency settings for running tests on Sparc
JDK-8212218[TESTBUG] runtime/ErrorHandling/TestHeapDumpOnOutOfMemoryErrorInMetaspace.java timed out
JDK-8213422compilercontrol/DontInlineDirectiveTest.java needs a longer default timeout