Tomcat優(yōu)化身堡，配置優(yōu)化
1.內(nèi)存優(yōu)化
JAVA_OPTS="-server -Xms2048M -Xmx2048M -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=$CATALINA_HOME/logs/heap.dump"
2.并發(fā)優(yōu)化
${tomcat}/webapps/docs/config/http.html
maxConnections：最大并發(fā)連接數(shù)团赁，NIO和NIO2默認(rèn)10000著淆，APR/native模式是8192惨险，The maximum number of connections that the server will accept and process at any given time
acceptCount: 隊(duì)列最大排隊(duì)數(shù)句各，默認(rèn)值是100寞缝，The maximum queue length for incoming connection requests when all possible request processing threads are in use.
maxThreads：最大工作線(xiàn)程數(shù)，The maximum number of request processing threads to be created by this Connector
minSpareThreads：最小空閑的工作線(xiàn)程所刀。The minimum number of threads always kept running
3.其他優(yōu)化，
${tomcat}/webapps/docs/config/host.html
autoDeploy：This flag value indicates if Tomcat should check periodically for new or updated web applications while Tomcat is running
${tomcat}/webapps/docs/config/http.html
enableLookups：false
${tomcat}/webapps/docs/config/context.html:
reloadable：默認(rèn)false捞挥，開(kāi)發(fā)階段可以設(shè)置true浮创，負(fù)載很重
4. connector：apr
http://apr.apache.org/
依賴(lài)：
APR 1.2+ development headers (libapr1-dev package)
OpenSSL 1.0.2+ development headers (libssl-dev package)
JNI headers from Java compatible JDK 1.4+
GNU development environment (gcc, make)
yum install apr* openssl-devel gcc make
tar zxvf apr-1.4.5.tar
cd apr-1.4.5
./configure --prefix=/usr/local/apr
make
make install
tar -zxvf apr-iconv-1.2.1.tar.gz
cd apr-iconv-1.2.1
./configure --prefix=/usr/local/apr-iconv --with-apr=/usr/local/apr
make
make install
yum install expat-devel
tar zxvf apr-util-1.3.12.tar.gz
cd apr-util-1.3.12
./configure --prefix=/usr/local/apr-util --with-apr=/usr/local/apr
make
make install
安裝openssl 1.0.2
./config --prefix=/usr/local/openssl
修改Makefile：
vi Makefile
將原來(lái)的：CFLAG= -DOPENSSL_THREADS
修改為： CFLAG= -fPIC -DOPENSSL_THREADS
也就是添加-fPIC
執(zhí)行執(zhí)行：
make && make install
cd bin
tar -zxvf tomcat-native.tar.gz
cd tomcat-native-1.2.12-src
cd native
./configure --with-apr=/usr/local/apr --with-ssl=/usr/local/openssl
make
make install
catalina.sh：
JAVA_OPTS="$JAVA_OPTS -Djava.library.path=/usr/local/apr/lib
注意：開(kāi)啟了apr之后，jvm用到的native內(nèi)存會(huì)增大砌函，因此要適當(dāng)調(diào)大Metaspace空間,添加JVM選項(xiàng)：-XX:MetaspaceSize=128m
JAVA_OPTS="-server -Xms2048M -Xmx2048M -XX:MetaspaceSize=128M -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=$CATALINA_HOME/logs/heap.dump"
server.xml：
<Connector port="8080" protocol="org.apache.coyote.http11.Http11AprProtocol"
connectionTimeout="20000"
redirectPort="8443" />
<Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="off" />
LVS四層負(fù)載均衡
LVS + Keepalived高可用
