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<h2 class="title" style="clear: both"><a id="set_lg_max_parameter"></a>set_lg_max</h2>
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<p>
Sets the maximum size of a single file in the log, in bytes.
The value set for this parameter may not be larger than the
maximum unsigned four-byte value.
</p>
<p>
When the logging subsystem is configured for on-disk logging, the
default size of a log file is 10MB.
</p>
<p>
When the logging subsystem is configured for in-memory logging, the
default size of a log file is 256KB. In addition, the configured log
buffer size must be larger than the log file size. (The logging
subsystem divides memory configured for in-memory log records into
"files", as database environments configured for in-memory log records
may exchange log records with other members of a replication group,
and those members may be configured to store log records on-disk.)
When choosing log buffer and file sizes for in-memory logs,
applications should ensure the in-memory log buffer size is large
enough that no transaction will ever span the entire buffer, and avoid
a state where the in-memory buffer is full and no space can be freed
because a transaction that started in the first log "file" is still
active.
</p>
<p>
The syntax of this parameter in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is a
single line with the string <code class="literal">set_lg_max</code>,
one or more whitespace characters, and the maximum log
file size in bytes.
</p>
<p>
If the database environment already exists when this parameter is
changed, it is ignored. To change this value after the environment
has been created, re-create your environment.
</p>
<p>For more information, see <a class="xref" href="envset_lg_max.html" title="DbEnv::set_lg_max()">DbEnv::set_lg_max()</a>. </p>
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