Sun Microsystems Netscape Enterprise Server, Руководство администратора

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Using perfdump Statistics to Tune Your Server
242 Netscape Enterprise Server Administrator’s Guide
Enterprise Server uses NSPR, which is an underlying portability layer that
provides access to the host OS services. This layer provides abstractions for
threads that are not always the same asthose for the OS-provided threads.
These non-native threads have lower scheduling overhead so their use
improves performance. However, these threads are sensitive to blocking calls
to the OS, such as I/O calls. To make it easier to write NSAPI extensions that
can make use of blocking calls, the server keeps a pool of threads that safely
support blocking calls (usually this means it is a native OS thread). During
request processing, any NSAPI function that is not marked as being safe for
execution on a non-native thread is scheduled for execution on one of the
threads in the native thread pool.
If you have written your own NSAPI plug-ins such as
NameTrans
,
Service
,
or
PathCheck
functions, these execute by default on a thread from the native
thread pool. If your plug-in makes use of the NSAPI functions for I/O
exclusively or does not use the NSAPI I/O functions at all, then it can execute
on a non-native thread. For this to happen, the function must be loaded with a
“
NativeThread=no
” option indicating that it does not require a native thread.
To do this, add this to the “
load-modules
” Init line in the
obj.conf
file:
Init funcs="pcheck_uri_clean_fixed_init" shlib="C:/Netscape/p186244/
P186244.dll" fn="load-modules" NativeThread="no"
The
NativeThread
flag affects all functions in the
funcs
list, so if you have
more than one function in a library but only some of them use native threads,
use separate Init lines.
Idle/Peak/Limit
Idle indicates the number of threads that are currently idle. Peak indicates the
peak number in the pool. Limit indicates the maximum number of native
threads allowed in the thread pool, and is determined by the setting of the
NSCP_POOL_THREADMAX
environment variable.
Tuning
Modify the
NSCP_POOL_THREADMAX
environment variable.