database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-27 12:41:57 +03:00
Code Activity

Rename pg_restore -m to -j, and add documentation about what good numbers

Browse Source 
are.  per discussion on hackers
This commit is contained in:
Peter Eisentraut
2009-03-20 09:21:09 +00:00
parent 753a040486
commit 249d936bed
4 changed files with 56 additions and 38 deletions
Download Patch File Download Diff File Expand all files Collapse all files

64
doc/src/sgml/ref/pg_restore.sgml
View File

@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/pg_restore.sgml,v 1.80 2009/02/26 16:02:37 petere Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/pg_restore.sgml,v 1.81 2009/03/20 09:21:08 petere Exp $ -->
<refentry id="APP-PGRESTORE">
<refmeta>
@ -215,6 +215,46 @@
</listitem>
</varlistentry>
<varlistentry>
<term><option>-j <replaceable class="parameter">number-of-jobs</replaceable></option></term>
<term><option>--jobs=<replaceable class="parameter">number-of-jobs</replaceable></option></term>
<listitem>
<para>
Run the most time-consuming parts
of <application>pg_restore</> &mdash; those which load data,
create indexes, or create constraints &mdash; using multiple
concurrent jobs. This option can dramatically reduce the time
to restore a large database to a server running on a
multi-processor machine.
</para>
<para>
Each job is one process or one thread, depending on the
operating system, and uses a separate connection to the
server.
</para>
<para>
The optimal value for this option depends on the hardware
setup of the server, of the client, and of the network.
Factors include the number of CPU cores and the disk setup. A
good place to start is the number of CPU cores on the server,
but values larger than that can also lead to faster restore
times in many cases. Of course, values that are too high will
lead to decreasing performance because of thrashing.
</para>
<para>
Only the custom archive format is supported with this option.
The input file must be a regular file (not, for example, a
pipe). This option is ignored when emitting a script rather
than connecting directly to a database server. Also, multiple
jobs cannot be used together with the
option <option>--single-transaction</option>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>-l</option></term>
<term><option>--list</option></term>
@ -241,28 +281,6 @@
</listitem>
</varlistentry>
<varlistentry>
<term><option>-m <replaceable class="parameter">number-of-threads</replaceable></option></term>
<term><option>--multi-thread=<replaceable class="parameter">number-of-threads</replaceable></option></term>
<listitem>
<para>
Run the most time-consuming parts of <application>pg_restore</>
&mdash; those which load data, create indexes, or create
constraints &mdash; using multiple concurrent connections to the
database. This option can dramatically reduce the time to restore a
large database to a server running on a multi-processor machine.
</para>
<para>
This option is ignored when emitting a script rather than connecting
directly to a database server. Multiple threads cannot be used
together with <option>--single-transaction</option>. Also, the input
must be a plain file (not, for example, a pipe), and at present only
the custom archive format is supported.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>-n <replaceable class="parameter">namespace</replaceable></option></term>
<term><option>--schema=<replaceable class="parameter">schema</replaceable></option></term>