Netscape ENTERPRISE SERVER 6.1, Руководство пользователя

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Init SAFs
Chapter 7 Syntax and Use of magnus.conf 261
thread-pool-init
Applicable in
Init
-class directives.
This function creates a new pool of user threads. A pool must be declared before
it’s used. To tell a plugin to use the new pool, specify the
pool
parameter when
loading the plugin with the Init-class function
load-modules
.
One reason to create a custom thread pool would be if a plugin is not thread-aware,
in which case you can set the maximum number of threads in the pool to 1.
The older parameter
NativeThread=yes
always engages one default native pool,
called
NativePool
.
The native pool on UNIX is normally not engaged, as all threads are OS-level
threads. Using native pools on UNIX may introduce a small performance overhead
as they’ll require an additional context switch; however, they can be used to
localize the
jvm.stickyAttach
effect or for other purposes, such as resource
control and management or to emulate single-threaded behavior for plug-ins.
On Windows NT/Windows 2000, the default native pool is always being used and
Enterprise Server uses fibers (user-scheduled threads) for initial request
processing. Using custom additional pools on Windows NT/Windows 2000
introduces no additional overhead.
In addition, native thread pool parameters can be added to the
magnus.conf
file
for convenience. For more information, see “Native Thread Pools,” on page 274 in
Chapter 7, “Syntax and Use of magnus.conf.”
Parameters
name
name of the thread pool.
maxthreads
maximum number of threads in the pool.
Enterprise Server
minthreads
minimum number of threads in the pool.
queueSize
size of the queue for the pool. If all the threads in the pool
are busy, further request-handling threads that want to get a
thread from the pool will wait in the pool queue. The
number of request-handling threads that can wait in the
queue is limited by the queue size. If the queue is full, the
next request-handling thread that comes to the queue is
turned away, with the result that the request is turned
down, but the request-handling thread remains free to
handle another request instead of becoming locked up in the
queue.