--- old/src/share/vm/runtime/commandLineFlagConstraintsGC.cpp 2016-03-17 16:44:30.537521514 -0700 +++ new/src/share/vm/runtime/commandLineFlagConstraintsGC.cpp 2016-03-17 16:44:30.397521519 -0700 @@ -606,9 +606,15 @@ "greater than or equal to reserved area in TLAB (" SIZE_FORMAT ")\n", value, ThreadLocalAllocBuffer::alignment_reserve_in_bytes()); return Flag::VIOLATES_CONSTRAINT; - } else { - return Flag::SUCCESS; } + if (value > (ThreadLocalAllocBuffer::max_size() * HeapWordSize)) { + CommandLineError::print(verbose, + "MinTLABSize (" SIZE_FORMAT ") must be " + "less than or equal to ergonomic TLAB maximum (" SIZE_FORMAT ")\n", + value, ThreadLocalAllocBuffer::max_size() * HeapWordSize); + return Flag::VIOLATES_CONSTRAINT; + } + return Flag::SUCCESS; } Flag::Error TLABSizeConstraintFunc(size_t value, bool verbose) {