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Swap Device & Unix Disk Buffer

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Old 11-02-2005
Swap Device & Unix Disk Buffer
Does anyone know if when the Swap Device / Page file in unix is carrying out Page / Swap In's and Page / Swap outs, does it go through the Unix Disk Cache ( I am presuming raw partitions are not being used ) ?

Therefore if there is paging activity on a system ( measured by sar -p, sar -g and vmstat -p ), should this activity also be reflected at the Unix Disk Cache level ( measured through sar -b ) and ultamately at the disk io level ( measured through sar -d and iostat ).

Alternatively does the swap partition bypass the Unix Cache altogether ?

One other question - how does onboard disk caches ( i.e. chips embedded with the disk itself ) effect the unix cache and how do you measure this activity ?
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text::pdf::page

Text::PDF::Page(3pm)					User Contributed Perl Documentation				      Text::PDF::Page(3pm)

NAME

       Text::PDF::Page - Represents a PDF page, inherits from Text::PDF::Pages

DESCRIPTION

       Represents a page of output in PDF. It also keeps track of the content stream, any resources (such as fonts) being switched, etc.

       Page inherits from Pages due to a number of shared methods. They are really structurally quite different.

INSTANCE VARIABLES

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METHODS

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perl v5.8.8							    2006-09-09						      Text::PDF::Page(3pm)