diff options
Diffstat (limited to 'doc/src/sgml/maintenance.sgml')
| -rw-r--r-- | doc/src/sgml/maintenance.sgml | 26 |
1 files changed, 8 insertions, 18 deletions
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index dfa2e259ff..1affca872a 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/maintenance.sgml,v 1.24 2003/08/31 17:32:19 petere Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/maintenance.sgml,v 1.25 2003/09/12 22:17:23 tgl Exp $ --> <chapter id="maintenance"> @@ -347,9 +347,8 @@ SELECT datname, age(datfrozenxid) FROM pg_database; <programlisting> play=# VACUUM; -WARNING: Some databases have not been vacuumed in 1613770184 transactions. - Better vacuum them within 533713463 transactions, - or you may have a wraparound failure. +WARNING: some databases have not been vacuumed in 1613770184 transactions +HINT: Better vacuum them within 533713463 transactions, or you may have a wraparound failure. VACUUM </programlisting> </para> @@ -387,20 +386,11 @@ VACUUM </indexterm> <para> - <productname>PostgreSQL</productname> is unable to reuse B-tree index - pages in certain cases. The problem is that if indexed rows are - deleted, those index pages can only be reused by rows with similar - values. For example, if indexed rows are deleted and newly - inserted/updated rows have much higher values, the new rows can't use - the index space made available by the deleted rows. Instead, such - new rows must be placed on new index pages. In such cases, disk - space used by the index will grow indefinitely, even if - <command>VACUUM</> is run frequently. - </para> - <para> - As a solution, you can use the <command>REINDEX</> command - periodically to discard pages used by deleted rows. There is also - <filename>contrib/reindexdb</> which can reindex an entire database. + In some situations it is worthwhile to rebuild indexes periodically + with the <command>REINDEX</> command. (There is also + <filename>contrib/reindexdb</> which can reindex an entire database.) + However, <productname>PostgreSQL</> 7.4 has substantially reduced the need + for this activity compared to earlier releases. </para> </sect1> |