Sun Microsystems Netscape Enterprise Server, Руководство администратора

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About RqThrottle
230 Netscape Enterprise Server Administrator’s Guide
number of requests. If it has reached the limit, it defers processing new
requests until the number of active requests drops below the maximum
amount.
In theory, you could set the maximum simultaneous requests to 1 and still have
a functional server. Setting this value to 1 would mean that the server could
only handle one request at a time, but since HTTP requests generally have a
very short duration (response time can be as low as 5 milliseconds), processing
one request at a time would still allow you to process up to 200 requests per
second.
However, in actuality, Internet clients frequently connect to the server and then
do not complete their requests. In these cases, the server waits 30 seconds or
more for the data before timing out. (You can define this timeout period in
obj.conf
. It has a default of 5 minutes.) Also, some sites do heavyweight
transactions that take minutes to complete. Both of these factors add to the
maximum simultaneous requests that are required. If your site is processing
many requests that take many seconds, you may need to increase the number
of maximum simultaneous requests.
In the 3.0 server the defaults were 48/128. With 4.0, the limits are increased to
48/512. This is because 128 can be a gating factor for performance even on
sites with as few as 750,000 hits per day. If your site is experiencing slowness
and the
ActiveThreads
count remains close to the limit, consider increasing
the maximum threads limit. To find out the active thread count, use the
perfdump utility.
A suitable
RqThrottle
value ranges from 200-2000 depending on the load. If
you want your server to use all the available resources on the system (that is,
you don’t run other server software on the same machine), then you can
increase
RqThrottle
to a larger value than necessary without negative
consequences.
Note
If you are using older NSAPI plugins that are not reentrant, they will not work
with the multithreading model described in this document. To continue using
them, you should revise them so that they are reentrant. If this is not possible,
you can configure your server to work with them by setting
RqThrottle
to 1
and then using a high value for
MaxProcs
, such as 48 or greater, but this will
adversely impact your server’s performance.