DbEnv::log_stat
|
![API](../images/api.gif)
|
#include <db_cxx.h>
int
DbEnv::log_stat(DB_LOG_STAT **spp, u_int32_t flags);
Description
The DbEnv::log_stat method
creates a statistical structure and copies a pointer to it into a
user-specified memory location.
The flags value must be set to 0 or
the following value:
- DB_STAT_CLEAR
- Reset statistics after returning their values.
Statistical structures are created 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
library function 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 log region statistics are stored in a structure of type DB_LOG_STAT.
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_max;
- The maximum size of any individual file comprising the log.
- 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_cur_offset;
- The byte offset of the last record known to be on disk.
- u_int32_t st_flushcommit;
- The number of log flushes that contained a transaction commit record.
- 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 DbEnv::log_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.
Errors
The DbEnv::log_stat method may fail and throw an exception or return a non-zero error for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the DbEnv::log_stat method may fail and either
return DB_RUNRECOVERY or throw an exception encapsulating
DB_RUNRECOVERY, in which case all subsequent Berkeley DB calls will fail
in the same way.
Class
DbEnv
See Also
DbEnv::set_lg_bsize,
DbEnv::set_lg_dir,
DbEnv::set_lg_max,
DbEnv::set_lg_regionmax,
DbEnv::log_archive,
DbEnv::log_compare,
DbEnv::log_cursor,
DbEnv::log_file,
DbEnv::log_flush,
DbEnv::log_put,
DbEnv::log_register,
DbEnv::log_stat,
DbEnv::log_unregister,
DbLogc::logc_close
and
DbLogc::logc_get.
Copyright Sleepycat Software