Im passing “-Xgenconfig:64m,64m,semispaces:128m,512m,markcompact -Xmx900m” to 1.2. Can you tell me what options should be passed to 1.3/1.4 to have a similar setup?
“64m,64m,semispaces” means a young generation consisting of a semispaces collector with an initial semi-space size 64m and a maximum semi-space size of 64m. In 1.2, generation sizing does not include any scratch areas, and in a standard semispace collector 50% of the space is scratch. In 1.3/1.4, generation sizing includes scratch (you can argue either way). For 1.3, the similar setting would be: -XX:NewSize=128m -XX:MaxNewSize=128m The SurvivorRatio is 64 for sparc-solaris, meaning that you get a 124mb eden and two 2mb semispaces. That is pretty small, but should work fine. To get closer to 1.2 behavior one can in addition set -XX:SurvivorRatio=2 which will provide a 64mb eden and two 32mb semispaces. The default value for MaxNewSize is 32mb (in 1.3 Solaris Sparc, 2.5mb on 1.3 Intel), so the 1.2 setting above gives a 4X larger new generation. “128m,512m,markcompact” means a mark-compact old generation with initial 128mb size and max 512mb size. In 1.3/1.4, the old generation is sized
