These are the flags used in the HP SPECjbb2000 submission: -Xmn The amount of space allocated to the "New" generation in the 2-generation garbage collector. -XX:+ServerApp Setting in the VM  for long-running server-side applications which can benefit from more aggressive inlining and compilation. vm_bigpg_enabled allows the system to use pages sizes > 8K vm_bigpg_thresh the percentage of memory which vm will attempt to keep on the pagelists (default to 6%) vps_pagesize=64 virtual page size in kilobytes vps_ceiling=65536 maximum memory in kilobytes devoted to large pages