HP Integrity NonStop H-Series - Manual (Page 317)

to NSJSP through TS/MP and there will not be any file system call. After the 25 requests are
serviced, subsequent requests on those 25 web dialogs are delivered to NSJSP through file system
I/O operations.
At this stage, all 25 links to the NSJSP instance are free to process more incoming requests
delivered through TS/MP. Therefore, the NSJSP instance must be able to handle 25 more
concurrent requests, all being the first requests of web dialogs. After the 25 requests are also
processed, the subsequent requests on these new connections arrive at NSJSP through file system
I/O. At this stage, NSJSP could be handling up to 50 concurrent requests and all these requests
are being delivered through file system calls from
httpd and not through TS/MP. Hence, the
25 links are free to process new web dialogs. Therefore, a single instance of NSJSP can serve all
the 100 requests.
At this point, one instance of NSJSP could be processing requests from all the possible 100
connections to the
httpd processes. This means that there could be a scenario where all the 100
requests time out. Therefore, there must be enough space in the $RECEIVE file to handle (100+100)
messages. Therefore, TANDEM_RECEIVE_DEPTH must have a value of 200. The reason for setting
TANDEM_RECEIVE_DEPTH to a value of 200 can be explained as:
To handle 100 requests, you need 100 threads. In an extreme case of all the 100 requests timing
out, you need another 100 threads to process the new incoming 100 requests because the threads
processing the timeout requests could still be busy. Therefore, the number of threads that need
to be configured is (100+100 = 200).
Configuring Java Runtime Arguments
The configurations for Java runtime arguments can be done in the <iTP WebServer
deployment directory>/conf/servlet.config file on OSS. The sscaux object is
configured under the Server directive. Java runtime arguments are populated in the Arglist .
Some of the important Java runtime arguments that you must consider during the deployment
of your Hibernate applications are:
• -Xmx
• -Xss
• -Xnoclassgc
There are other Java runtime arguments supported by NSJSP. For more information, see the
NonStop Servlets for JavaServer Pages (NSJSP) 6.0 System Administrator's Guide.
-Xmx
Sets the maximum size of the memory allocation pool, which is the garbage collected heap.
Syntax:
-Xmx maximum-heap-size [ k | m ]
where,
maximum-heap-size is the maximum size of the memory allocated for the garbage collected.
It must be greater than or equal to 1000 bytes.
k sets the value of maximum-heap-size to be read in kilobytes.
m sets the value of maximum-heap-size to be read in megabytes.
-Xss
Sets the maximum stack size that can be used by a Java thread.
Syntax:
-Xmx maximum-stack-size
where,
maximum-stack-size is the maximum size of the stack trace in kilobytes.
NonStop Platform Configurations 317