openvz tomcat假死状态问题

买可一台2G内存的openvz VPS，安装了centos系统。部署了nginx和tomcat+apr，页面的响应速度很快.但是空闲一段时间之后，无访问状态，再次访问时。tomcat就像假死一样，nginx代理超时，8080端口等待1分钟到10多分钟才有响应。是不是OPENVZ的内存管理模式问题还是我配置有问题？tomcat配置如下：
catalina.sh

export JAVA_OPTS="-server -Xms1400M -Xmx1400M -Xss512k -XX:+AggressiveOpts -XX:+UseBiasedLocking -XX:PermSize=128M -XX:MaxPermSize=256M -XX:+DisableExplicitGC -XX:MaxTenuringThreshold=31 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC  -XX:+CMSParallelRemarkEnabled -XX:+UseCMSCompactAtFullCollection -XX:LargePageSizeInBytes=128m  -XX:+UseFastAccessorMethods -XX:+UseCMSInitiatingOccupancyOnly -Djava.awt.headless=true"

serviver.xml

<Connector port="8080" protocol="HTTP/1.1"
               connectionTimeout="60000"
               keepAliveTimeout="15000"
               maxkeepAliveRequests="1"
               maxHttpHeaderSize="8192"
               UrIEncoding="UTF-8"
               redirectPort="8443"
               enableLookups="false"
               disableUploadTimeout="true"
               miniSpareThreads="25"
               maxSpareThreads="75"
               acceptCount="360"
               maxThreads="360"
               maxprocessors="1024"
               minProcessors="8"
               userURIValidationHack="false" />

<Executor name="tomcatThreadPool" namePrefix="catalina-exec-"
        maxThreads="500" minSpareThreads="20" maxldleTime="6000"/>

这里应该是错了把？这两个是冲突还是一个起效？