Sun Microsystems Netscape Enterprise Server, Руководство администратора

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Using perfdump Statistics to Tune Your Server
244 Netscape Enterprise Server Administrator’s Guide
Tuning
Turn this parameter on by adding this directive to
magnus.conf
:
PostThreadsEarly 1
Thread Pool Environmental Variables
NSCP_POOL_WORKQUEUEMAX
This value defaults to 0x7FFFFFFF (a very large number). Setting this below the
RqThrottle
value causes the server to execute a busy function instead of the
intended NSAPI function whenever the number of requests waiting for service
by pool threads exceeds this value. The default returns a “503 Service
Unavailable” response and logs a message if
LogVerbose
is enabled. Setting
this
above
RqThrottle
causes the server to reject connections before a busy
function can execute.
This value represents the maximum number of concurrent requests for service
which require a native thread. If your system is unable to fulfill requests due to
load, letting more requests queue up increases the latency for requests and
could result in all available request threads waiting for a native thread. In
general, set this value to be high enough to avoid rejecting requests under
“normal” conditions, which would be the anticipated maximum number of
concurrent users who would execute requests requiring a native thread.
The difference between this value and
RqThrottle
is the number of requests
reserved for non-native thread requests (such as static html, gif, and jpeg files).
Keeping a reserve (and rejecting requests) ensures that your server continues to
fill requests for static files, which prevents it from becoming unresponsive
during periods of very heavy dynamic content load. If your server consistently
rejects connections, this value is set too low or your server hardware is
overloaded.
NSCP_POOL_THREADMAX
This value represents the maximum number of threads in the pool. Set this
value as low as possible to sustain the optimal volume of requests. A higher
value allows more requests to execute concurrently, but has more overhead
due to context switching, so “bigger is not always better.” If you are not
saturating your CPU but you are seeing requests queue up, then increase this
number. Typically, you will not need to increase this number.