Jetty的threadpool模块

Jetty提供的线程池相关的模块，如下：

threadpool
threadpool-virtual，使用JDK 21提供的virtual threads。
threadpool-virtual-preview，使用JDK 19和JDK 20。

注意上述模块不能共存。

启用threadpool模块后再启用threadpool-virtual模块时，将会有类似如下的提示：

ERROR : Module threadpool-virtual provides threadpool, which is already provided by threadpool enabled in [${jetty.base}/start.d/threadpool.ini]

Usage: java -jar $JETTY_HOME/start.jar [options] [properties] [configs]

       java -jar $JETTY_HOME/start.jar --help  # for more information

threadpool

启用threadpool模块，执行如下命令：

java -jar $JETTY_HOME/start.jar --add-modules=threadpool

命令的输出，如下：

INFO  : threadpool      initialized in ${jetty.base}/start.d/threadpool.ini

INFO  : Base directory was modified

threadpool模块的配置文件$JETTY_BASE/start.d/threadpool.ini，内容如下：

# ---------------------------------------

# Module: threadpool

# Enables and configures the Server ThreadPool.

# ---------------------------------------

--modules=threadpool

## Thread name prefix.

#jetty.threadPool.namePrefix=qtp<hashCode>

## Minimum number of pooled threads.

#jetty.threadPool.minThreads=10

## Maximum number of pooled threads.

#jetty.threadPool.maxThreads=200

## Number of reserved threads (-1 for heuristic).

#jetty.threadPool.reservedThreads=-1

## Whether to use virtual threads, if the runtime supports them.

## Deprecated, use Jetty module 'threadpool-virtual' instead.

#jetty.threadPool.useVirtualThreads=false

## Thread idle timeout (in milliseconds).

#jetty.threadPool.idleTimeout=60000

## The max number of idle threads that are evicted in one idleTimeout period.

#jetty.threadPool.maxEvictCount=1

## Whether to output a detailed dump.

#jetty.threadPool.detailedDump=false

各参数的说明，如下：

jetty.threadPool.namePrefix

线程池中各线程的名称前缀。
jetty.threadPool.minThreads

线程池中线程的最小数量。
jetty.threadPool.maxThreads

线程池中线程的最大数量。
jetty.threadPool.reservedThreads

线程池中保留的线程的数量。
jetty.threadPool.useVirtualThreads

不推荐使用。对于JDK 21，推荐使用threadpool-virtual模块。
jetty.threadPool.idleTimeout

空闲线程从线程池中移除前等待的时长，单位：毫秒，默认值：60000，即60秒。
jetty.threadPool.maxEvictCount

清理空闲线程时，单次操作中被移除掉的线程的数量。
jetty.threadPool.detailedDump

是否导出线程池中各线程的完整的栈。默认值为false，即只输出栈顶。

threadpool-virtual

启用threadpool-virtual模块，执行如下命令：

java -jar $JETTY_HOME/start.jar --add-modules=threadpool-virtual

启用threadpool-virtual模块成功时的输出，如下：

INFO  : threadpool-virtual initialized in ${jetty.base}/start.d/threadpool-virtual.ini

INFO  : Base directory was modified

threadpool-virtual模块的配置文件$JETTY_BASE/start.d/threadpool-virtual.ini，内容如下：

# ---------------------------------------

# Module: threadpool-virtual

# Enables and configures the Server ThreadPool with support for virtual threads in Java 21 or later.

# ---------------------------------------

--modules=threadpool-virtual

## Platform threads name prefix.

#jetty.threadPool.namePrefix=qtp<hashCode>

## Minimum number of pooled threads.

#jetty.threadPool.minThreads=10

## Maximum number of pooled threads.

#jetty.threadPool.maxThreads=200

## Number of reserved threads (-1 for heuristic).

#jetty.threadPool.reservedThreads=-1

## Thread idle timeout (in milliseconds).

#jetty.threadPool.idleTimeout=60000

## The max number of idle threads that can be evicted in one idleTimeout period.

#jetty.threadPool.maxEvictCount=1

## Whether to output a detailed dump.

#jetty.threadPool.detailedDump=false

## Virtual threads name prefix.

#jetty.threadPool.virtual.namePrefix=qtp<hashCode>-virtual-

## Whether virtual threads inherits the values of inheritable thread locals.

#jetty.threadPool.virtual.inheritInheritableThreadLocals=true

各参数的说明，如下：

jetty.threadPool.namePrefix

同threadPool。
jetty.threadPool.minThreads

同threadPool。
jetty.threadPool.maxThreads

同threadPool。
jetty.threadPool.reservedThreads

同threadPool。
jetty.threadPool.idleTimeout

同threadPool。
jetty.threadPool.maxEvictCount

同threadPool。
jetty.threadPool.detailedDump

同threadPool。
jetty.threadPool.virtual.namePrefix

virtual threads的线程名称的前缀。
jetty.threadPool.virtual.inheritInheritableThreadLocals

是否复用ThreadLocal对象。默认值为true。

threadpool-virtual-preview

启用threadpool-virtual-preview模块，执行如下命令：

java -jar $JETTY_HOME/start.jar --add-modules=threadpool-virtual-preview

启用threadpool-virtual-preview模块成功时的输出，如下：

INFO  : threadpool-virtual-preview initialized in ${jetty.base}/start.d/threadpool-virtual-preview.ini

INFO  : Base directory was modified

threadpool-virtual-preview模块的配置文件$JETTY_BASE/start.d/threadpool-virtual-preview.ini，内容如下：

# ---------------------------------------

# Module: threadpool-virtual-preview

# Enables and configures the Server ThreadPool with support for virtual threads in Java 19 and Java 20.

# ---------------------------------------

--modules=threadpool-virtual-preview

## Platform threads name prefix.

#jetty.threadPool.namePrefix=qtp<hashCode>

## Minimum number of pooled threads.

#jetty.threadPool.minThreads=10

## Maximum number of pooled threads.

#jetty.threadPool.maxThreads=200

## Number of reserved threads (-1 for heuristic).

#jetty.threadPool.reservedThreads=-1

## Thread idle timeout (in milliseconds).

#jetty.threadPool.idleTimeout=60000

## The max number of idle threads that can be evicted in one idleTimeout period.

#jetty.threadPool.maxEvictCount=1

## Whether to output a detailed dump.

#jetty.threadPool.detailedDump=false

## Virtual threads name prefix.

#jetty.threadPool.virtual.namePrefix=qtp<hashCode>-virtual-

## Whether virtual threads are allowed to set thread locals.

#jetty.threadPool.virtual.allowSetThreadLocals=true

## Whether virtual threads inherits the values of inheritable thread locals.

#jetty.threadPool.virtual.inheritInheritableThreadLocals=true

各参数的说明，如下：

jetty.threadPool.namePrefix

同threadPool。
jetty.threadPool.minThreads

同threadPool。
jetty.threadPool.maxThreads

同threadPool。
jetty.threadPool.reservedThreads

同threadPool。
jetty.threadPool.idleTimeout

同threadPool。
jetty.threadPool.maxEvictCount

同threadPool。
jetty.threadPool.detailedDump

同threadPool。
jetty.threadPool.virtual.namePrefix

virtual threads的线程名称的前缀。
jetty.threadPool.virtual.allowSetThreadLocals

是否允许virtual threads记录ThreadLocal类型的对象。默认值为true。
jetty.threadPool.virtual.inheritInheritableThreadLocals

是否复用ThreadLocal对象。默认值为true。

参考资料