From: Hans Schaechl (hans.schaechl@kippdata.de)
Date: Thu May 08 2003 - 02:54:34 EDT
Dear list,
does someone know why SUN still publishes the maximum
value for maxpgio as 1024?
http://docs.sun.com/db/doc/816-7137/6md5pauiq?a=view
Even after Solaris 8's new page scanner algorithm made our
all-time favourite tunable "priority_paging" superfluous,
maxpgio and fastscan still remain valid targets of tuning
for heavily loaded systems, IMHO.
As we all know there are several practical guidelines
recommending to set maxpgio to much higher values, including
SUN's Sun/Oracle Best Practices BluePrint, Adrian's performance
tuning tips, Aptitune's SarCheck recommendations etc.etc.
I had some conversation with SUN support about this issue
in the last time, and they still tell customers not to set this
parameter larger than 1k.
The author of the above mentioned blueprint comments
on that as follows:
"The reccomendation is limited to pre-Solaris 8. While it
is widely documented that settings past 1024 (or 2048?) cannot
possibly have any value, the empirical results contradict that.
The maxpgio setting is involved in some calcalations beyond what
is documented, and the exact reason the larger setting is helpful
is poorly understood."
Maybe someone wants to share his/her inside view and knowledge
about that particular tunable!
Thanks a lot in advance!
Hans
-- Hans Schaechl Tel: 0228-98549-0 kippdata GmbH Fax: 0228-98549-50 Bornheimer Str. 33a Email: hans.schaechl@kippdata.de D-53111 Bonn http://www.kippdata.de/ _______________________________________________ sunmanagers mailing list sunmanagers@sunmanagers.org http://www.sunmanagers.org/mailman/listinfo/sunmanagers
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