Java &引用；“打开的文件太多”；从Tomcat 7迁移到Tomcat 9之后

从Tomact 7迁移到Tomcat 9.0.20（使用相同的Java版本1.8.0_25运行）后，我们在Linux RHEL 7上的JSF2 web应用程序出现了问题。一段时间后，我们会遇到如下异常：

java.io.FileNotFoundException: /f4m/tomcat/tomcat_f4mbs/webapps/ACM/WEB-INF/acm-config.xml (Too many open files)
    at java.io.FileInputStream.open0(Native Method)
    at java.io.FileInputStream.open(FileInputStream.java:195)
    at java.io.FileInputStream.<init>(FileInputStream.java:138)
    at java.io.FileInputStream.<init>(FileInputStream.java:93)

这不是完整的列表-还有很多

列出的文件数量会上下波动。 对我来说，只要页面在浏览器中显示，xhtml（或其使用的组件之一）似乎就有一个打开的文件描述符

如果我再次在Tomcat7上部署相同的应用程序，我只能看到JAR文件、套接字的开放文件描述符，但不能看到xhtml的开放文件描述符

---

问题出在哪里？

文件泄漏发生在JSF2 MyFaces实现中，另请参见此处：

---

我能够通过使用这个工具找到问题：

比较/etc/init.d/tomcat（我假设在RHEL上也是如此）和$tomcat_HOME/conf/*以查看是否有任何变化。通常，您必须将ulimit指令添加到/etc/init.d/tomcat，它可能在7中，但在9中没有？可能其中一个conf文件发生了变化？问题不是，限制已经改变了。问题是Tomact 7从来没有为xhtml文件创建过一个打开的文件描述符——按钮Tomcat 9是这样做的……您是否收到任何关于缓存不够大的启动警告？我记得必须添加一个指令，将缓存大小从7升级到8（9也是如此）。conf/context.xml（context | Resources元素），我设置了cachingAllowed=“true”和cacheMaxSize=“100000”属性，并能够运行应用程序，但这只是在tomcat提供静态内容的情况下，理想情况下前面应该有一个web服务器这样做。

ls -l /proc/4025/fd


lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 238 -> /usr/java/jdk1.8.0_25/jre/lib/resources.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 239 -> pipe:[3661823]
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 24 -> /f4m/tomcat/tomcat_f4mbscrm/lib/websocket-api.jar
l-wx------. 1 f4mHttp f4mHttp 64 May 16 09:01 240 -> pipe:[3661823]
lrwx------. 1 f4mHttp f4mHttp 64 May 16 09:01 241 -> anon_inode:[eventpoll]
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 243 -> pipe:[3661824]
l-wx------. 1 f4mHttp f4mHttp 64 May 16 09:01 244 -> pipe:[3661824]
lrwx------. 1 f4mHttp f4mHttp 64 May 16 09:01 245 -> anon_inode:[eventpoll]
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 246 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/msgBox.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 247 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/msgBox.xhtml
lrwx------. 1 f4mHttp f4mHttp 64 May 16 09:01 248 -> socket:[3667364]
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 249 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/searchpage.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 25 -> /f4m/tomcat/tomcat_f4mbscrm/lib/jasper.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 250 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/searchpage.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 251 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/portal/nav/portalheader.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 252 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/portal/customizing/nav/menu.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 253 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 254 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/nav/bottomPanel.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 255 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/nav/bottomPanel.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 256 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/msgBox.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:01 257 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 258 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 259 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 26 -> /f4m/tomcat/tomcat_f4mbscrm/lib/ecj-4.9.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 260 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 261 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 262 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/common/barcodefunction_incl.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 263 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/portal/nav/portalfooterAll.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 264 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/partner/crmpartner.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 266 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/partner/crmpartner.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 267 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/portal/nav/portalheader.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 268 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/portal/customizing/nav/menu.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 27 -> /f4m/tomcat/tomcat_f4mbscrm/lib/catalina-ha.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 274 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/partner/crmpartner_topnav.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 275 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/msgBox.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 276 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/msgBox.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 277 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 278 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 279 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 28 -> /f4m/tomcat/tomcat_f4mbscrm/lib/jsp-api.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 280 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 281 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 282 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 283 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 286 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 287 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 288 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 289 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 29 -> /f4m/tomcat/tomcat_f4mbscrm/lib/annotations-api.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 290 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 291 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 292 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 293 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/partner/crmpartnerparent_incl.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 294 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 295 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 296 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 297 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 298 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/partner/crmpartnerHierarchySimilarAddresses.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 299 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/partner/crmpartnerchild_incl.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 3 -> /usr/java/jdk1.8.0_25/jre/lib/rt.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 30 -> /f4m/tomcat/tomcat_f4mbscrm/lib/tomcat-i18n-fr.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 300 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 301 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 302 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 303 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 304 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/form/partner/crmpartnerHierarchySimilarAddresses.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 305 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 306 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 307 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 308 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 309 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 31 -> /f4m/tomcat/tomcat_f4mbscrm/lib/tomcat-coyote.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 310 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 311 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 312 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 313 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 314 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 315 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 316 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 317 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 318 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 319 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 08:58 32 -> /f4m/tomcat/tomcat_f4mbscrm/lib/catalina-ant.jar
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 320 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 321 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 322 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 323 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 324 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 325 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 326 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 327 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 328 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml
lr-x------. 1 f4mHttp f4mHttp 64 May 16 09:02 329 -> /f4m/tomcat/tomcat_f4mbscrm/webapps/ACM/resources/components/calendar.xhtml