Basic System Problem Analysis - August 2003

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Virtual Space Management Structures: continued
VSM uses VPN (virtual page number) Cache entries for portions of objects that are either
in memory or on the way in to memory. These cache entries provide a fast means of
linking the VSM structures such as the VSOD with the physical page addresses that the
object occupies in real memory.
The VAINFO function is useful for finding out information about objects however
certain information is unavailable in DEBUG. See HELP VAINFO for more details.
A couple useful macros to note are:
VS_PAGE_INFO which format virtual and secondary storage information for a given
virtual address.
VS_ALLOCATION formats information about PID usage as well as SR6 and SR7
allocations.