Berkeley DB: DB_ENV->log

DB_ENV->log_stat

#include <db.h> int DB_ENV->log_stat(DB_ENV *env, DB_LOG_STAT **statp, u_int32_t flags); Description: DB_ENV->log_stat The DB_ENV->log_stat method returns the logging subsystem statistics. The DB_ENV->log_stat method creates a statistical structure of type DB_LOG_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 DB_ENV->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_LOG_STAT fields will be filled in: u_int32_t st_magic; The magic number that identifies a file as a log file. u_int32_t st_version; The version of the log file type. int st_mode; The mode of any created log files. u_int32_t st_lg_bsize; The in-memory log record cache size. u_int32_t st_lg_size; The current log file size. u_int32_t st_w_mbytes; The number of megabytes written to this log. u_int32_t st_w_bytes; The number of bytes over and above st_w_mbytes written to this log. u_int32_t st_wc_mbytes; The number of megabytes written to this log since the last checkpoint. u_int32_t st_wc_bytes; The number of bytes over and above st_wc_mbytes written to this log since the last checkpoint. u_int32_t st_wcount; The number of times the log has been written to disk. u_int32_t st_wcount_fill; The number of times the log has been written to disk because the in-memory log record cache filled up. u_int32_t st_scount; The number of times the log has been flushed to disk. u_int32_t st_cur_file; The current log file number. u_int32_t st_cur_offset; The byte offset in the current log file. u_int32_t st_disk_file; The log file number of the last record known to be on disk. u_int32_t st_disk_offset; The byte offset of the last record known to be on disk. u_int32_t st_maxcommitperflush; The maximum number of commits contained in a single log flush. u_int32_t st_mincommitperflush; The minimum number of commits contained in a single log flush that contained a commit. u_int32_t st_regsize; The size of the region. u_int32_t st_region_wait; The number of times that a thread of control was forced to wait before obtaining the region lock. u_int32_t st_region_nowait; The number of times that a thread of control was able to obtain the region lock without waiting. The DB_ENV->log_stat method returns a non-zero error value on failure and 0 on success. Parameters flags The flags parameter must be set to 0 or the following value: DB_STAT_CLEAR Reset statistics after returning their values. statp The statp parameter references memory into which a pointer to the allocated statistics structure is copied. Errors The DB_ENV->log_stat method may fail and return one of the following non-zero errors: EINVAL An invalid flag value or parameter was specified. Class DB_ENV, DB_LOGC, DB_LSN See Also Logging Subsystem and Related Methods