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Select a topic below to see Questions Frequently Asked by partners

» Using the online documentation library(installing BNU from the asap SDK)
» Global sections(how to create and use.)
» xx$CREATE_BUFOBJ system service(usage)
» Ethernet address(methods of determination)
» Shareable images(cookbook approach to creating one)
» Sharing data/code at absolute addresses(a guide with examples)
» Determining the Alpha microprocessor
» Using GETSYI to get hardware status

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Ask the Wizard Questions

Tuning: Extent cache

The Question is:

When I do a SHOW DEVICE/FULL DIA9, the listing shows information
about the number of blocks in the extent cache. Where do I
find more information about WHAT the extent cache is?

The Answer is:

    $ mcr sysgen help param acp_extcache


        ACP_EXTCACHE sets the number of entries in the extent cache.
        Each entry points to one contiguous area of free space on disk.
        A specification of 0 means no cache. Too small a value causes
        excessive XQP I/O operations, while too large a value causes
        excessive physical memory to be consumed by the extent cache.

    Also see Kirby McCoy's File System Internals book.