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<p>Library Version 11.2.5.2</p>
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<th colspan="3" align="center">DbEnv::log_stat()</th>
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<div class="sect1" lang="en" xml:lang="en">
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<h2 class="title" style="clear: both"><a id="logstat"></a>DbEnv::log_stat()</h2>
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<pre class="programlisting">#include &lt;db_cxx.h&gt;
int
DbEnv::log_stat(DB_LOG_STAT **statp, u_int32_t flags); </pre>
<p>
The <code class="methodname">DbEnv::log_stat()</code> method returns the logging subsystem
statistics.
</p>
<p>
The <code class="methodname">DbEnv::log_stat()</code> method creates a statistical structure of type
<code class="literal">DB_LOG_STAT</code> and copies a pointer to it into a user-specified memory
location.
</p>
<p>
Statistical structures are stored in allocated memory. If
application-specific allocation routines have been declared (see
<a class="xref" href="envset_alloc.html" title="DbEnv::set_alloc()">DbEnv::set_alloc()</a>
for more information), they are used to allocate the memory;
otherwise, the standard C library <span class="bold"><strong>malloc</strong></span>(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.
</p>
<p>
The following <code class="literal">DB_LOG_STAT</code> fields will be filled in:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<span class="bold"><strong>u_int32_t st_cur_file;</strong></span>
</p>
<p>
The current log file number.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_cur_offset;</strong></span>
</p>
<p>
The byte offset in the current log file.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_disk_file;</strong></span>
</p>
<p>
The log file number of the last record known to be on disk.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_disk_offset;</strong></span>
</p>
<p>
The byte offset of the last record known to be on disk.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_fileid_init;</strong></span>
</p>
<p>
The initial allocated file logging identifiers.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_lg_bsize;</strong></span>
</p>
<p>
The in-memory log record cache size.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_lg_size;</strong></span>
</p>
<p>
The log file size.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_magic;</strong></span>
</p>
<p>
The magic number that identifies a file as a log file.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_maxcommitperflush;</strong></span>
</p>
<p>
The maximum number of commits contained in a single log flush.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_maxnfileid;</strong></span>
</p>
<p>
The maximum number of file logging identifiers
used.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_mincommitperflush;</strong></span>
</p>
<p>
The minimum number of commits contained in a single log flush that
contained a commit.
</p>
</li>
<li>
<p>
<span class="bold"><strong>int st_mode;</strong></span>
</p>
<p>
The mode of any created log files.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_nfileid;</strong></span>
</p>
<p>
The current number of file logging identifiers.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_rcount;</strong></span>
</p>
<p>
The number of times the log has been read from disk.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_record;</strong></span>
</p>
<p>
The number of records written to this log.
</p>
</li>
<li>
<p>
<span class="bold"><strong>roff_t st_regsize;</strong></span>
</p>
<p>
The region size, in bytes.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_region_wait;</strong></span>
</p>
<p>
The number of times that a thread of control was forced to wait before
obtaining the log region mutex.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_region_nowait;</strong></span>
</p>
<p>
The number of times that a thread of control was able to obtain the
log region mutex without waiting.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_scount;</strong></span>
</p>
<p>
The number of times the log has been flushed to disk.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_version;</strong></span>
</p>
<p>
The version of the log file type.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_w_bytes;</strong></span>
</p>
<p>
The number of bytes over and above <span class="bold"><strong>st_w_mbytes</strong></span> written to this log.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_w_mbytes;</strong></span>
</p>
<p>
The number of megabytes written to this log.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_wc_bytes;</strong></span>
</p>
<p>
The number of bytes over and above <span class="bold"><strong>st_wc_mbytes</strong></span> written to this log since the last
checkpoint.
</p>
</li>
<li>
<p>
<span class="bold"><strong>u_int32_t st_wc_mbytes;</strong></span>
</p>
<p>
The number of megabytes written to this log since the last checkpoint.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_wcount_fill;</strong></span>
</p>
<p>
The number of times the log has been written to disk because the
in-memory log record cache filled up.
</p>
</li>
<li>
<p>
<span class="bold"><strong>uintmax_t st_wcount;</strong></span>
</p>
<p>
The number of times the log has been written to disk.
</p>
</li>
</ul>
</div>
<p>
The <code class="methodname">DbEnv::log_stat()</code> method may not be called before the
<a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> method is called.
</p>
<p>
The <code class="methodname">DbEnv::log_stat()</code> <span>
<span>
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.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3620894"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3620617"></a>statp</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>statp</strong></span> parameter references memory
into which a pointer to the allocated statistics structure is copied.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3619949"></a>flags</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
or the following value:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p><a id="logstat_DB_STAT_CLEAR"></a>
<code class="literal">DB_STAT_CLEAR</code>
</p>
<p>
Reset statistics after returning their values.
</p>
</li>
</ul>
</div>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3621043"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DbEnv::log_stat()</code> <span>
<span>
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors:
</span>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3621171"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
An invalid flag value or parameter was specified.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3621149"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>,
<a class="link" href="logc.html" title="The DbLogc Handle">DbLogc</a>,
<a class="link" href="lsn.html" title="Chapter 8.  The DbLsn Handle">DbLsn</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3621045"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="lsn.html#loglist" title="Logging Subsystem and Related Methods">Logging Subsystem and Related Methods</a>
</p>
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