minix/external/public-domain/sqlite/man/SQLITE_STATUS_MEMORY_USED.3
2018-11-18 02:11:42 +00:00

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.Dd March 11, 2017
.Dt SQLITE_STATUS_MEMORY_USED 3
.Os
.Sh NAME
.Nm SQLITE_STATUS_MEMORY_USED ,
.Nm SQLITE_STATUS_PAGECACHE_USED ,
.Nm SQLITE_STATUS_PAGECACHE_OVERFLOW ,
.Nm SQLITE_STATUS_SCRATCH_USED ,
.Nm SQLITE_STATUS_SCRATCH_OVERFLOW ,
.Nm SQLITE_STATUS_MALLOC_SIZE ,
.Nm SQLITE_STATUS_PARSER_STACK ,
.Nm SQLITE_STATUS_PAGECACHE_SIZE ,
.Nm SQLITE_STATUS_SCRATCH_SIZE ,
.Nm SQLITE_STATUS_MALLOC_COUNT
.Nd Status Parameters
.Sh SYNOPSIS
.Fd #define SQLITE_STATUS_MEMORY_USED
.Fd #define SQLITE_STATUS_PAGECACHE_USED
.Fd #define SQLITE_STATUS_PAGECACHE_OVERFLOW
.Fd #define SQLITE_STATUS_SCRATCH_USED
.Fd #define SQLITE_STATUS_SCRATCH_OVERFLOW
.Fd #define SQLITE_STATUS_MALLOC_SIZE
.Fd #define SQLITE_STATUS_PARSER_STACK
.Fd #define SQLITE_STATUS_PAGECACHE_SIZE
.Fd #define SQLITE_STATUS_SCRATCH_SIZE
.Fd #define SQLITE_STATUS_MALLOC_COUNT
.Sh DESCRIPTION
These integer constants designate various run-time status parameters
that can be returned by sqlite3_status().
.Bl -tag -width Ds
.It SQLITE_STATUS_MEMORY_USED
This parameter is the current amount of memory checked out using sqlite3_malloc(),
either directly or indirectly.
The figure includes calls made to sqlite3_malloc()
by the application and internal memory usage by the SQLite library.
Scratch memory controlled by SQLITE_CONFIG_SCRATCH
and auxiliary page-cache memory controlled by SQLITE_CONFIG_PAGECACHE
is not included in this parameter.
The amount returned is the sum of the allocation sizes as reported
by the xSize method in sqlite3_mem_methods.
.It SQLITE_STATUS_MALLOC_SIZE
This parameter records the largest memory allocation request handed
to sqlite3_malloc() or sqlite3_realloc()
(or their internal equivalents).
Only the value returned in the *pHighwater parameter to sqlite3_status()
is of interest.
The value written into the *pCurrent parameter is undefined.
.It SQLITE_STATUS_MALLOC_COUNT
This parameter records the number of separate memory allocations currently
checked out.
.It SQLITE_STATUS_PAGECACHE_USED
This parameter returns the number of pages used out of the pagecache memory allocator
that was configured using SQLITE_CONFIG_PAGECACHE.
The value returned is in pages, not in bytes.
.It SQLITE_STATUS_PAGECACHE_OVERFLOW
This parameter returns the number of bytes of page cache allocation
which could not be satisfied by the SQLITE_CONFIG_PAGECACHE
buffer and where forced to overflow to sqlite3_malloc().
The returned value includes allocations that overflowed because they
where too large (they were larger than the "sz" parameter to SQLITE_CONFIG_PAGECACHE)
and allocations that overflowed because no space was left in the page
cache.
.It SQLITE_STATUS_PAGECACHE_SIZE
This parameter records the largest memory allocation request handed
to pagecache memory allocator.
Only the value returned in the *pHighwater parameter to sqlite3_status()
is of interest.
The value written into the *pCurrent parameter is undefined.
.It SQLITE_STATUS_SCRATCH_USED
This parameter returns the number of allocations used out of the scratch memory allocator
configured using SQLITE_CONFIG_SCRATCH.
The value returned is in allocations, not in bytes.
Since a single thread may only have one scratch allocation outstanding
at time, this parameter also reports the number of threads using scratch
memory at the same time.
.It SQLITE_STATUS_SCRATCH_OVERFLOW
This parameter returns the number of bytes of scratch memory allocation
which could not be satisfied by the SQLITE_CONFIG_SCRATCH
buffer and where forced to overflow to sqlite3_malloc().
The values returned include overflows because the requested allocation
was too larger (that is, because the requested allocation was larger
than the "sz" parameter to SQLITE_CONFIG_SCRATCH)
and because no scratch buffer slots were available.
.It SQLITE_STATUS_SCRATCH_SIZE
This parameter records the largest memory allocation request handed
to scratch memory allocator.
Only the value returned in the *pHighwater parameter to sqlite3_status()
is of interest.
The value written into the *pCurrent parameter is undefined.
.It SQLITE_STATUS_PARSER_STACK
The *pHighwater parameter records the deepest parser stack.
The *pCurrent value is undefined.
The *pHighwater value is only meaningful if SQLite is compiled with
YYTRACKMAXSTACKDEPTH.
.El
.Pp
New status parameters may be added from time to time.
.Sh SEE ALSO
.Xr sqlite3_malloc 3 ,
.Xr sqlite3_mem_methods 3 ,
.Xr sqlite3_malloc 3 ,
.Xr sqlite3_status 3 ,
.Xr SQLITE_CONFIG_SINGLETHREAD 3