DbEnv::mutex_stat API Ref

#include <db_cxx.h>

int DbEnv::mutex_stat(DB_MUTEX_STAT **statp, u_int32_t flags);

int DbEnv::mutex_stat_print(u_int32_t flags);


Description: DbEnv::mutex_stat

The DbEnv::mutex_stat method returns the mutex subsystem statistics.

The DbEnv::mutex_stat method creates a statistical structure of type DB_MUTEX_STAT and copies a pointer to it into a user-specified memory location.

Statistical structures are stored in allocated memory. If application-specific allocation routines have been declared (see DbEnv::set_alloc for more information), they are used to allocate the memory; otherwise, the standard C library malloc(3) is used. The caller is responsible for deallocating the memory. To deallocate the memory, free the memory reference; references inside the returned memory need not be individually freed.

The following DB_MUTEX_STAT fields will be filled in:


u_int32_t st_mutex_align; u_int32_t st_mutex_tas_spins; int st_mutex_cnt; u_int32_t st_mutex_free; u_int32_t st_mutex_inuse; u_int32_t st_mutex_inuse_max; roff_t st_regsize; u_int32_t st_region_wait; u_int32_t st_region_nowait;

The DbEnv::mutex_stat method may not be called before the DbEnv::open method is called.

The DbEnv::mutex_stat method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.

Parameters
flags statp

Errors

The DbEnv::mutex_stat method may fail and throw DbException, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:


EINVAL

Description: DbEnv::mutex_stat_print

The DbEnv::mutex_stat_print method displays the mutex subsystem statistical information, as described for the DbEnv::mutex_stat method. The information is printed to a specified output channel (see the DbEnv::set_msgfile method for more information), or passed to an application callback function (see the DbEnv::set_msgcall method for more information).

The DbEnv::mutex_stat_print method may not be called before the DbEnv::open method is called.

The DbEnv::mutex_stat_print method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.

Parameters
flags


Class DbEnv
See Also Database Environments and Related Methods

APIRef

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