Veritas Storage Foundation for Oracle 5.0 Administrator's Guide, HP-UX 11i v3, Second Edition, December 2008

Increases or decreases the maximum size of an extent. When
the file system is following its default allocation policy for
sequential writes to a file, it allocates an initial extent that
is large enough for the first write to the file. When additional
extents are allocated, they are progressively larger (the
algorithm tries to double the size of the file with each new
extent) so each extent can hold several writes' worth of data.
This is done to reduce the total number of extents in
anticipation of continued sequential writes. When the file
stops being written, any unused space is freed for other files
to use. Normally, this allocation stops increasing the size
of extents at 2048 blocks, which prevents one file from
holding too much unused space. max_seqio_extent_size
is measured in file system blocks.
max_seqio_extent_size
Enables or disables caching on Quick I/O files. The default
behavior is to disable caching. To enable caching, set
qio_cache_enable to 1. On systems with large memories,
the database cannot always use all of the memory as a cache.
By enabling file system caching as a second level cache,
performance may be improved. If the database is performing
sequential scans of tables, the scans may run faster by
enabling file system caching so the file system will perform
aggressive read-ahead on the files.
qio_cache_enable
Tuning for performance
About tuning VxFS
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