/etc/zexpl/rse.env

The environment variables defined in rse.env are used by RSE, Java™, and z/OS® UNIX. The defaults used by z/OS Explorer are targeted at small to medium sized installations that do not require the optional components of z/OS Explorer. "rse.env, RSE configuration file" in the Host Configuration Guide (SC27-8437) describes each variable that is defined in the sample file, where the following variables require special attention:

#_RSE_JAVAOPTS="$_RSE_JAVAOPTS -Xms128m -Xmx512m"
Set initial (Xms) and maximum (Xmx) heap size. The defaults are 128M and 512M respectively. Uncomment and change to enforce the desired heap size values.
#_RSE_JAVAOPTS="$_RSE_JAVAOPTS -Dmaximum.clients=30"
Maximum amount of clients serviced by one thread pool. The default is 30. Uncomment and customize to limit the number of clients per thread pool. Note that other limits may prevent RSE from reaching this limit.
#_RSE_JAVAOPTS="$_RSE_JAVAOPTS -Dmaximum.threads=600"
Maximum amount of active threads in one thread pool to allow new clients. The default is 600. Uncomment and customize to limit the number of clients per thread pool based upon the number of threads in use. Note that each client connection uses multiple threads and that other limits may prevent RSE from reaching this limit.
Note: This value must be lower than the setting for MAXTHREADS and MAXTHREADTASKS in SYS1.PARMLIB(BPXPRMxx).
#_RSE_JAVAOPTS="$_RSE_JAVAOPTS -Dminimum.threadpool.process=1"
The minimum number of active thread pools. The default is 1. Uncomment and customize to start at least the listed number of thread pool processes. Thread pool processes are used for load balancing the RSE server threads. More new processes are started when they are needed. Starting the new processes up front helps prevent connection delays but uses more resources during idle times.
Note: If the single.logon directive is active, then there will be at least 2 thread pools started, even if minimum.threadpool.process is set to 1. The default setting for single.logon in rse.env is active.
#_RSE_JAVAOPTS="$_RSE_JAVAOPTS -Dmaximum.threadpool.process=100"
The maximum number of active thread pools. The default is 100. Uncomment and customize to limit the number of thread pool processes. Thread pool processes are used for load balancing the RSE server threads, so limiting them will limit the amount of active client connections.