SAS 9.1.3 Intelligence Platform: System Administration Guide

CHAPTER
13 Using Configuration Settings to
Optimize Metadata Server
Performance
Configuring the Number of Threads Used by the Metadata Server 103
About the MAXACTIVETHREADS, THREADSMIN, and THREADSMAX Options 103
Change the MAXACTIVETHREADS, THREADSMIN, and THREADSMAX Options 104
Using Workunit Journaling to Optimize Performance on Multiprocessor Hosts 104
What Is Workunit Journaling? 104
Configure Workunit Journaling 105
Avoiding Changes to the Repository That Adversely Affect Performance 107
Determining Whether the COMPRESS or REUSE Attribute Has Been Set 107
Repairing Problematic Data Sets 107
Configuring the Number of Threads Used by the Metadata Server
About the MAXACTIVETHREADS, THREADSMIN, and THREADSMAX
Options
The way in which the metadata server uses threads is determined by the values of
the following options:
3 The MAXACTIVETHREADS server configuration option specifies the maximum
number of metadata server threads that are allowed to run concurrently on the
metadata server. The number of processors available on the server host machine
determines the number of queries that can be active at any time.
3 The OBJECTSERVERPARMS options THREADSMIN and THREADSMAX, which
are specified in the metadata server invocation command, determine the number
of threads that are maintained in the server’s thread pool. The thread pool defines
the total number of threads that are available to a server, regardless of the
number of user requests that are received or accepted.
By default, MAXACTIVETHREADS is set to number-of-processors, and THREADSMIN and
THREADSMAX are set to (number-of-processors *2)+1.
The settings of THREADSMIN and THREADSMAX optimize performance by
ensuring that the number of available threads is compatible with the number of threads
that can be accepted concurrently by the metadata server. Setting THREADSMIN and
THREADSMAX to the same value prevents the metadata server from creating and
destroying threads that might not be used. A THREADSMAX setting that is slightly
higher than the number of processors on the metadata server ensures that an active
thread is always available to the server. If clients experience significant delays in
response from the metadata server and not all of the processors are used at 100 percent
capacity, you can increase the THREADSMIN and THREADSMAX settings to try to get
better utilization.
103