</para>

<para>

This feature allows backends to queue multiple read requests, which allows for more efficient sequential scans, bitmap heap scans, and vacuums.

This is enabled by server variable io_method, with server variables io_combine_limit and io_max_combine_limit added to control it. This also enables

effective_io_concurrency and maintenance_io_concurrency values greater than zero for systems without fadvise() support. The new system view pg_aios shows the file handles being used

for asynchronous I/O.

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Author: Melanie Plageman <melanieplageman@gmail.com>

2025-03-12 [9219093ca] Modularize log_connections output

Author: Melanie Plageman <melanieplageman@gmail.com>

2025-03-12 [18cd15e70] Add connection establishment duration logging

-->

<listitem>

<para>

Increase the logging granularity of server variable log_connections (Melanie Plageman)

<ulink url="&commit_baseurl;9219093ca">&sect;</ulink>

<ulink url="&commit_baseurl;18cd15e70">&sect;</ulink>

</para>

<para>

This server variable was previously only boolean; these options are still supported.

</para>

</listitem>

<!--

Author: Melanie Plageman <melanieplageman@gmail.com>

2025-03-12 [18cd15e70] Add connection establishment duration logging

-->

<listitem>

<para>

Add log_connections option to report the duration of connection stages (Melanie Plageman)

<ulink url="&commit_baseurl;18cd15e70">&sect;</ulink>

</para>

</listitem>

<!--

Author: Tom Lane <tgl@sss.pgh.pa.us>

2025-04-07 [3516ea768] Add local-address escape "%L" to log_line_prefix.