Websphere 能安裝的 AP 總數計算方式

這是從 Websphere Journal 網路版本中節錄出來的，計算server中總共能裝多少AP

Total Physical Memory		4096 MB
Other processes (operating system and other processes) memory	OS + process 1 + process 2 ...	400 MB
Deployment Manager Memory (if co-resident)	DM Max heap + Java interpreter	0 (DM not co-resident)
Node Agent Memory	NA Max heap + Java interpreter	128 + 42 = 170 MB
Memory Available for Application Servers	Total memory - other processes - node agent memory	4096MB - 400 - 170 = 3430MB
Single Application Server Memory	App Srv Max heap + Java interpreter	256 + 64 = 320 MB
Maximum Number of Application Servers	(Available memory/Single application server memory) * margin for safety	(3430/320) * 0.8 = 8 application server maximum

The total memory used is equal to the current heap size plus the Java interpreter. The size of the Java interpreter depends on the heap size. For example, a 256MB heap typically has approximately 64 MB additional from the interpreter, whereas a 128MB heap will have approximately 42 MB. Therefore, an application server with a maximum heap size of 256MB can grow to approximately 320MB of physical memory. A 128MB node agent will grow to approximately 170MB.

via: http://www.findarticles.com/p/articles/mi_m0QVB/is_6_3/ai_n6123202