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<title>Berkeley DB: DbEnv::log_stat</title>
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<h1>DbEnv::log_stat</h1>
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#include <db_cxx.h>
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DbEnv::log_stat(DB_LOG_STAT **spp, u_int32_t flags);
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<p>The DbEnv::log_stat method returns the logging subsystem statistics.
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<p>The <b>flags</b> value must be set to 0 or
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<p><dt><a name="DB_STAT_CLEAR">DB_STAT_CLEAR</a><dd>Reset statistics after returning their values.
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<p>The DbEnv::log_stat method creates a statistical structure of type
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DB_LOG_STAT and copies a pointer to it into a user-specified memory
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<p>Statistical structures are created in allocated memory. If application-specific allocation
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routines have been declared (see <a href="../api_cxx/env_set_alloc.html">DbEnv::set_alloc</a> for more
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information), they are used to allocate the memory; otherwise, the
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library <b>malloc</b>(3) interface is used. The caller is
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responsible for deallocating the memory. To deallocate the memory, free
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the memory reference; references inside the returned memory need not be
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<p>The following DB_LOG_STAT fields will be filled in:
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<dt>u_int32_t st_magic;<dd>The magic number that identifies a file as a log file.
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<dt>u_int32_t st_version;<dd>The version of the log file type.
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<dt>int st_mode;<dd>The mode of any created log files.
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<dt>u_int32_t st_lg_bsize;<dd>The in-memory log record cache size.
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<dt>u_int32_t st_lg_size;<dd>The current log file size.
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<dt>u_int32_t st_w_mbytes;<dd>The number of megabytes written to this log.
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<dt>u_int32_t st_w_bytes;<dd>The number of bytes over and above <b>st_w_mbytes</b> written to this log.
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<dt>u_int32_t st_wc_mbytes;<dd>The number of megabytes written to this log since the last checkpoint.
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<dt>u_int32_t st_wc_bytes;<dd>The number of bytes over and above <b>st_wc_mbytes</b> written to this log
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since the last checkpoint.
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<dt>u_int32_t st_wcount;<dd>The number of times the log has been written to disk.
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<dt>u_int32_t st_wcount_fill;<dd>The number of times the log has been written to disk because the
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in-memory log record cache filled up.
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<dt>u_int32_t st_scount;<dd>The number of times the log has been flushed to disk.
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<dt>u_int32_t st_cur_file;<dd>The current log file number.
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<dt>u_int32_t st_cur_offset;<dd>The byte offset in the current log file.
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<dt>u_int32_t st_disk_file;<dd>The log file number of the last record known to be on disk.
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<dt>u_int32_t st_disk_offset;<dd>The byte offset of the last record known to be on disk.
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<dt>u_int32_t st_cur_offset;<dd>The byte offset of the last record known to be on disk.
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<dt>u_int32_t st_maxcommitperflush;<dd>The maximum number of commits contained in a single log flush.
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<dt>u_int32_t st_mincommitperflush;<dd>The minimum number of commits contained in a single log flush that
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<dt>u_int32_t st_regsize;<dd>The size of the region.
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<dt>u_int32_t st_region_wait;<dd>The number of times that a thread of control was forced to wait before
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obtaining the region lock.
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<dt>u_int32_t st_region_nowait;<dd>The number of times that a thread of control was able to obtain
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the region lock without waiting.
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<p>The DbEnv::log_stat method either returns a non-zero error value or throws an exception that
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encapsulates a non-zero error value on failure, and returns 0 on success.
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<p>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.
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If a catastrophic error has occurred, the DbEnv::log_stat method may fail and
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either return <a href="../ref/program/errorret.html#DB_RUNRECOVERY">DB_RUNRECOVERY</a> or throw a
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<a href="../api_cxx/runrec_class.html">DbRunRecoveryException</a>,
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in which case all subsequent Berkeley DB calls will fail in the same way.
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<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/logc_class.html">DbLogc</a>, <a href="../api_cxx/lsn_class.html">DbLsn</a>
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<a href="../api_cxx/log_list.html">Logging Subsystem and Related Methods</a>
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