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Comment:Use SQLITE_DEFAULT_PAGE_SIZE instead of 1024 in the page size algorithm.
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SHA1: c4bd8f4f2685ad352227811bff72d45f5ea02e1b
User & Date: drh 2008-04-29 13:18:58
Context
2008-05-08
14:24
Website change in preparation for version 3.5.9. check-in: 29af58951d user: drh tags: trunk
2008-04-29
13:18
Use SQLITE_DEFAULT_PAGE_SIZE instead of 1024 in the page size algorithm. check-in: c4bd8f4f26 user: drh tags: trunk
13:10
Add details to the page_size pragma, including specification of the page size selection algorithm. check-in: bc47f60abd user: drh tags: trunk
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    <p>If SQLite is compiled with the SQLITE_ENABLE_ATOMIC_WRITE option,
    then the default page size is chosen to be the largest page size
    less than or equal to SQLITE_MAX_DEFAULT_PAGE_SIZE for which atomic
    write is enabled according to the
    xDeviceCharacteristics method of the [sqlite3_io_methods] object for
    the database file.  If the SQLITE_ENABLE_ATOMIC_WRITE option is
    disabled or if xDeviceCharacteristics reports no suitable atomic
    write page sizes, then the default page size is the larger of 1024

    and the sector size as reported by the xSectorSize method of the
    [sqlite3_io_methods] object, but not more than 
    SQLITE_MAX_DEFAULT_PAGE_SIZE.  The default configuration for SQLite
    running on workstations is for atomic write to be
    disabled, for the maximum page size to be set to 32768, and for the

    maximum default page size to be set to 8192.  The default xSectorSize
    method on workstation implementations always reports a sector size
    of 512 bytes.  Hence, 
    the default page size chosen by SQLite is usually 1024 bytes.</p>
</li>

<tcl>Subsection max_page_count</tcl>







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    <p>If SQLite is compiled with the SQLITE_ENABLE_ATOMIC_WRITE option,
    then the default page size is chosen to be the largest page size
    less than or equal to SQLITE_MAX_DEFAULT_PAGE_SIZE for which atomic
    write is enabled according to the
    xDeviceCharacteristics method of the [sqlite3_io_methods] object for
    the database file.  If the SQLITE_ENABLE_ATOMIC_WRITE option is
    disabled or if xDeviceCharacteristics reports no suitable atomic
    write page sizes, then the default page size is the larger of 
    SQLITE_DEFALT_PAGE_SIZE
    and the sector size as reported by the xSectorSize method of the
    [sqlite3_io_methods] object, but not more than 
    SQLITE_MAX_DEFAULT_PAGE_SIZE.  The normal configuration for SQLite
    running on workstations is for atomic write to be
    disabled, for the maximum page size to be set to 32768, for
    SQLITE_DEFAULT_PAGE_SIZE to be 1024, and for the
    maximum default page size to be set to 8192.  The default xSectorSize
    method on workstation implementations always reports a sector size
    of 512 bytes.  Hence, 
    the default page size chosen by SQLite is usually 1024 bytes.</p>
</li>

<tcl>Subsection max_page_count</tcl>