Sybase Adaptive Server IQ 12.4.2, Administration And Performance Manual

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The process threading model
440
Figure 12-2: Multithreaded architecture
Multiple threads improve performance. Even a single-CPU machine gets better
performance by using threads.
Insufficient threads error
When you do not have enough server threads to initiate the query you have
issued, you get the error:
Not enough server threads available for this query
This condition may well be temporary. When some other query finishes,
threads are made available and the query may succeed the next time you issue
it. If the condition persists, you may need to restart the server and specify more
IQ threads, as described in the next section.
IQ options for managing thread usage
Adaptive Server IQ offers the following options to help you manage thread
usage.
• To set the maximum number of threads available for Adaptive Server IQ
use, set the server startup option
-iqmt
. This option is set automatically by
the
start_asiq
startup utility on the IBM UNIX platform only. The default
value is calculated from the number of connections and the number of
CPUs and is usually adequate. See the Adaptive Server IQ Installation and
Configuration Guide for the default value of
-iqmt
on your platform.