Hello, Thanks for your help. Here is a result of the command 'jmap -heap', could you help me to interpret this result, and to optimize my parameters? Best Regards, Jerome. Attaching to process ID 11776, please wait... Debugger attached successfully. Server compiler detected. JVM version is 1.5.0_11-b03 using parallel threads in the new generation. using thread-local object allocation. Mark Sweep Compact GC Heap Configuration: MinHeapFreeRatio = 40 MaxHeapFreeRatio = 70 MaxHeapSize = 2147483648 (2048.0MB) NewSize = 2686976 (2.5625MB) MaxNewSize = -65536 (-0.0625MB) OldSize = 1835008 (1.75MB) NewRatio = 2 SurvivorRatio = 8 PermSize = 21757952 (20.75MB) MaxPermSize = 134217728 (128.0MB) Heap Usage: New Generation (Eden + 1 Survivor Space): capacity = 644218880 (614.375MB) used = 581578344 (554.6363296508789MB) free = 62640536 (59.738670349121094MB) 90.27651347318476% used Eden Space: capacity = 572653568 (546.125MB) used = 572344744 (545.8304824829102MB) free = 308824 (0.29451751708984375MB) 99.94607140909318% used capacity = 71565312 (68.25MB) used = 9233600 (8.80584716796875MB) free = 62331712 (59.44415283203125MB) 12.902340172847985% used To Space: capacity = 71565312 (68.25MB) used = 0 (0.0MB) free = 71565312 (68.25MB) 0.0% used tenured generation: capacity = 1431699456 (1365.375MB) used = 254001848 (242.23503875732422MB) free = 1177697608 (1123.1399612426758MB) 17.741282706752667% used Perm Generation: capacity = 80216064 (76.5MB) used = 80136544 (76.42416381835938MB) free = 79520 (0.075836181640625MB) 99.90086773641748% used View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4024987#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...