Apache Tomcat 6 的記憶體配置 (效能調整)

Tomcat Server 預設可使用的記憶體為 128M,

若有大量網頁需求時, 會因記憶體太少, 而導致 Tomcat 當掉無法運作,

所以, 若要應付大量網頁的需求,需增加JVM的記憶體大小如下:

First Calculate the number of threads you can create

(MaxProcessMemory - JVMMemory - ReservedOsMemory) / (ThreadStackSize) = Number of threads

Example:

For Java 1.5 you will get the following results assuming that the OS reserves about 120MB:

1.5GB allocated to JVM: (2GB-1.5Gb-120MB)/(1MB) = ~380 threads

1.0GB allocated to JVM: (2GB-1.0Gb-120MB)/(1MB) = ~880 threads




Your Java Options Example: 

-Xms 512m
-Xmx 1024m
-Xss256k
-XX:MaxPermSize=256m
-XX:ReservedCodeCacheSize=128m 


另外一種方法，利用指令執行

於cmd下進入/bin

輸入 “tomcat6 //US//Tomcat6 –JvmMs 512 –jvmMx1024”

這兩個數值分別是最大與最小的heap size


如果是安裝是使用Windows服務帶起Tomcat，記得去註冊檔裡面修改參數