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diff --git a/docs/programmer_reference/log_config.html b/docs/programmer_reference/log_config.html index 361fb6af..d9052c15 100644 --- a/docs/programmer_reference/log_config.html +++ b/docs/programmer_reference/log_config.html @@ -14,7 +14,7 @@ <body> <div xmlns="" class="navheader"> <div class="libver"> - <p>Library Version 11.2.5.3</p> + <p>Library Version 12.1.6.1</p> </div> <table width="100%" summary="Navigation header"> <tr> @@ -22,9 +22,7 @@ </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="log.html">Prev</a> </td> - <th width="60%" align="center">Chapter 17. - The Logging Subsystem - </th> + <th width="60%" align="center">Chapter 17. The Logging Subsystem </th> <td width="20%" align="right"> <a accesskey="n" href="log_limits.html">Next</a></td> </tr> </table> @@ -38,39 +36,58 @@ </div> </div> </div> - <p>The aspects of logging that may be configured are the size of the -logging subsystem's region, the size of the log files on disk and the -size of the log buffer in memory. The <a href="../api_reference/C/envset_lg_regionmax.html" class="olink">DB_ENV->set_lg_regionmax()</a> method -specifies the size of the logging subsystem's region, in bytes. The -logging subsystem's default size is approximately 60KB. This value may -need to be increased if a large number of files are registered with the -Berkeley DB log manager, for example, by opening a large number of Berkeley DB -database files in a transactional application.</p> - <p>The <a href="../api_reference/C/envset_lg_max.html" class="olink">DB_ENV->set_lg_max()</a> method specifies the individual log file size for -all the applications sharing the Berkeley DB environment. Setting the log -file size is largely a matter of convenience and a reflection of the -application's preferences in backup media and frequency. However, -setting the log file size too low can potentially cause problems because -it would be possible to run out of log sequence numbers, which requires -a full archival and application restart to reset. See -<a class="xref" href="log_limits.html" title="Log file limits">Log file limits</a> for more -information.</p> - <p>The <a href="../api_reference/C/envset_lg_bsize.html" class="olink">DB_ENV->set_lg_bsize()</a> method specifies the size of the in-memory log -buffer, in bytes. Log information is stored in memory until the buffer -fills up or transaction commit forces the buffer to be written to disk. -Larger buffer sizes can significantly increase throughput in the -presence of long-running transactions, highly concurrent applications, -or transactions producing large amounts of data. By default, the buffer -is approximately 32KB.</p> - <p>The <a href="../api_reference/C/envset_lg_dir.html" class="olink">DB_ENV->set_lg_dir()</a> method specifies the directory in which -log files will be placed. By default, log files are placed in -the environment home directory.</p> - <p>The <a href="../api_reference/C/envset_lg_filemode.html" class="olink">DB_ENV->set_lg_filemode()</a> method specifies the absolute file mode for -created log files. This method is only useful for the rare Berkeley DB -application that does not control its umask value.</p> - <p>The <a href="../api_reference/C/envlog_set_config.html" class="olink">DB_ENV->log_set_config()</a> method configures several boolean parameters -that control the use of file system controls such as O_DIRECT and O_DSYNC, -automatic removal of log files, in-memory logging, and pre-zeroing of logfiles.</p> + <p> + The aspects of logging that may be configured are the size + of the logging subsystem's region, the size of the log files + on disk, the size of the log buffer in memory, and several + operating system settings affecting the behavior of log files. + </p> + <p> + The <a href="../api_reference/C/envset_lg_regionmax.html" class="olink">DB_ENV->set_lg_regionmax()</a> method specifies the size of the logging + subsystem's region, in bytes. The logging subsystem's default size + is approximately 60KB. This value may need to be increased if a + large number of files are registered with the Berkeley DB log + manager, for example, by opening a large number of Berkeley DB + database files in a transactional application. + </p> + <p> + The <a href="../api_reference/C/envset_lg_max.html" class="olink">DB_ENV->set_lg_max()</a> method specifies the individual log file + size for all the applications sharing the Berkeley DB + environment. Setting the log file size is largely a matter of + convenience and a reflection of the application's preferences + in backup media and frequency. However, setting the log file + size too low can potentially cause problems because it would + be possible to run out of log sequence numbers, which requires + a full archival and application restart to reset. See <a class="xref" href="log_limits.html" title="Log file limits">Log file limits</a> for more + information. + </p> + <p> + The <a href="../api_reference/C/envset_lg_bsize.html" class="olink">DB_ENV->set_lg_bsize()</a> method specifies the size of the + in-memory log buffer, in bytes. Log information is stored in + memory until the buffer fills up or transaction commit forces + the buffer to be written to disk. Larger buffer sizes can + significantly increase throughput in the presence of + long-running transactions, highly concurrent applications, or + transactions producing large amounts of data. By default, the + buffer is approximately 32KB. + </p> + <p> + The <a href="../api_reference/C/envset_lg_dir.html" class="olink">DB_ENV->set_lg_dir()</a> method specifies the directory in which + log files will be placed. By default, log files are placed in + the environment home directory. + </p> + <p> + The <a href="../api_reference/C/envset_lg_filemode.html" class="olink">DB_ENV->set_lg_filemode()</a> method specifies the absolute file + mode for created log files. This method is only useful for the + rare Berkeley DB application that does not control its umask + value. + </p> + <p> + The <a href="../api_reference/C/envlog_set_config.html" class="olink">DB_ENV->log_set_config()</a> method configures several boolean + parameters that control the use of file system controls such + as O_DIRECT and O_DSYNC, automatic removal of log files, + in-memory logging, and pre-zeroing of logfiles. + </p> </div> <div class="navfooter"> <hr /> @@ -83,9 +100,7 @@ automatic removal of log files, in-memory logging, and pre-zeroing of logfiles.< <td width="40%" align="right"> <a accesskey="n" href="log_limits.html">Next</a></td> </tr> <tr> - <td width="40%" align="left" valign="top">Chapter 17. - The Logging Subsystem - </td> + <td width="40%" align="left" valign="top">Chapter 17. The Logging Subsystem </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> |