Good news: this traces like a dream on TM trunk, with one modification to the peacekeeper harness. they call runTest() with an arg, but don't declare the function with one, so we fall off trace. Bug 481296 is required to fix this part. Fortunately, we can modify the peacekeeper harness and see how things would act if it were fixed. With the attached (modified) test case, we are about 15% behind v8 and very far behind webkit on mac. This comes down to bug 200505 (wasteful array.join behavior) and js_NewArrayObject. I will test on linux and see whether our lack of jemalloc is hurting us here. webkit is using tcmalloc.

fixed by bug 200505