|
1 | | -<!-- $PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.67 2009/04/09 22:32:02 momjian Exp $ --> |
| 1 | +<!-- $PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.68 2009/04/10 03:13:36 momjian Exp $ --> |
2 | 2 |
|
3 | 3 | <chapter id="monitoring"> |
4 | 4 | <title>Monitoring Database Activity</title> |
@@ -927,8 +927,9 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re |
927 | 927 | <function>pg_stat_get_blocks_fetched</function> minus |
928 | 928 | <function>pg_stat_get_blocks_hit</function> gives the number of kernel |
929 | 929 | <function>read()</> calls issued for the table, index, or |
930 | | - database; but the actual number of physical reads is usually |
931 | | - lower due to kernel-level buffering. |
| 930 | + database; the number of actual physical reads is usually |
| 931 | + lower due to kernel-level buffering. The <literal>*_blks_read</> |
| 932 | + statistics columns uses this subtraction, i.e. fetched minus hit. |
932 | 933 | </para> |
933 | 934 | </note> |
934 | 935 |
|
|