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Proofreading improvements for the Administration documentation book.

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This commit is contained in:
Bruce Momjian
2010-02-03 17:25:06 +00:00
parent 1e4cc384ab
commit bf62b1a078
16 changed files with 684 additions and 673 deletions
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doc/src/sgml/diskusage.sgml
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@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/diskusage.sgml,v 1.18 2007/01/31 20:56:16 momjian Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/diskusage.sgml,v 1.19 2010/02/03 17:25:05 momjian Exp $ -->
<chapter id="diskusage">
<title>Monitoring Disk Usage</title>
@ -18,10 +18,10 @@
<para>
Each table has a primary heap disk file where most of the data is
stored. If the table has any columns with potentially-wide values,
there is also a <acronym>TOAST</> file associated with the table,
there also might be a <acronym>TOAST</> file associated with the table,
which is used to store values too wide to fit comfortably in the main
table (see <xref linkend="storage-toast">). There will be one index on the
<acronym>TOAST</> table, if present. There might also be indexes associated
<acronym>TOAST</> table, if present. There also might be indexes associated
with the base table. Each table and index is stored in a separate disk
file &mdash; possibly more than one file, if the file would exceed one
gigabyte. Naming conventions for these files are described in <xref
@ -29,7 +29,7 @@
</para>
<para>
You can monitor disk space from three ways: using
You can monitor disk space three ways: using
SQL functions listed in <xref linkend="functions-admin-dbsize">,
using <command>VACUUM</> information, and from the command line
using the tools in <filename>contrib/oid2name</>. The SQL functions
@ -60,13 +60,15 @@ SELECT relfilenode, relpages FROM pg_class WHERE relname = 'customer';
like the following:
<programlisting>
SELECT relname, relpages
FROM pg_class,
(SELECT reltoastrelid FROM pg_class
WHERE relname = 'customer') ss
WHERE oid = ss.reltoastrelid
OR oid = (SELECT reltoastidxid FROM pg_class
WHERE oid = ss.reltoastrelid)
ORDER BY relname;
FROM pg_class,
(SELECT reltoastrelid
FROM pg_class
WHERE relname = 'customer') AS ss
WHERE oid = ss.reltoastrelid OR
oid = (SELECT reltoastidxid
FROM pg_class
WHERE oid = ss.reltoastrelid)
ORDER BY relname;
relname | relpages
----------------------+----------
@ -79,11 +81,11 @@ SELECT relname, relpages
You can easily display index sizes, too:
<programlisting>
SELECT c2.relname, c2.relpages
FROM pg_class c, pg_class c2, pg_index i
WHERE c.relname = 'customer'
AND c.oid = i.indrelid
AND c2.oid = i.indexrelid
ORDER BY c2.relname;
FROM pg_class c, pg_class c2, pg_index i
WHERE c.relname = 'customer' AND
c.oid = i.indrelid AND
c2.oid = i.indexrelid
ORDER BY c2.relname;
relname | relpages
----------------------+----------
@ -95,7 +97,9 @@ SELECT c2.relname, c2.relpages
It is easy to find your largest tables and indexes using this
information:
<programlisting>
SELECT relname, relpages FROM pg_class ORDER BY relpages DESC;
SELECT relname, relpages
FROM pg_class
ORDER BY relpages DESC;
relname | relpages
----------------------+----------
@ -105,9 +109,8 @@ SELECT relname, relpages FROM pg_class ORDER BY relpages DESC;
</para>
<para>
You can also use <filename>contrib/oid2name</> to show disk usage. See
<filename>README.oid2name</> in that directory for examples. It includes a script that
shows disk usage for each database.
You can also use <filename>contrib/oid2name</> to show disk usage; see
<xref linkend="oid2name"> for more details and examples.
</para>
</sect1>
@ -116,7 +119,7 @@ SELECT relname, relpages FROM pg_class ORDER BY relpages DESC;
<para>
The most important disk monitoring task of a database administrator
is to make sure the disk doesn't grow full. A filled data disk will
is to make sure the disk doesn't become full. A filled data disk will
not result in data corruption, but it might prevent useful activity
from occurring. If the disk holding the WAL files grows full, database
server panic and consequent shutdown might occur.
@ -140,7 +143,7 @@ SELECT relname, relpages FROM pg_class ORDER BY relpages DESC;
If your system supports per-user disk quotas, then the database
will naturally be subject to whatever quota is placed on the user
the server runs as. Exceeding the quota will have the same bad
effects as running out of space entirely.
effects as running out of disk space entirely.
</para>
</sect1>
</chapter>