-<!-- $PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.79 2010/04/15 20:56:13 petere Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.80 2010/04/26 19:56:55 tgl Exp $ -->
<chapter id="monitoring">
<title>Monitoring Database Activity</title>
$ ps auxww | grep ^postgres
postgres 960 0.0 1.1 6104 1480 pts/1 SN 13:17 0:00 postgres -i
postgres 963 0.0 1.1 7084 1472 pts/1 SN 13:17 0:00 postgres: writer process
-postgres 965 0.0 1.1 6152 1512 pts/1 SN 13:17 0:00 postgres: stats collector process
+postgres 965 0.0 1.1 6152 1512 pts/1 SN 13:17 0:00 postgres: stats collector process
postgres 998 0.0 2.3 6532 2992 pts/1 SN 13:18 0:00 postgres: tgl runbug 127.0.0.1 idle
postgres 1003 0.0 2.4 6532 3128 pts/1 SN 13:19 0:00 postgres: tgl regression [local] SELECT waiting
postgres 1016 0.1 2.4 6532 3080 pts/1 SN 13:19 0:00 postgres: tgl regression [local] idle in transaction
</para>
<para>
- The statistics collector communicates with the backends needing
+ The statistics collector communicates with the backends needing
information (including autovacuum) through temporary files.
These files are stored in the <filename>pg_stat_tmp</filename> subdirectory.
When the postmaster shuts down, a permanent copy of the statistics
<entry><structname>pg_stat_activity</></entry>
<entry>One row per server process, showing database OID, database
name, process <acronym>ID</>, user OID, user name, application name,
- current query, query's waiting status, time at which the current
- transaction and current query began execution, time at which the
- process was started, and client's address and port number.
+ client's address and port number, times at which the server process,
+ current transaction, and current query began execution, process's waiting
+ status, and text of the current query.
The columns that report data on the current query are available unless
the parameter <varname>track_activities</varname> has been turned off.
Furthermore, these columns are only visible if the user examining
Beginning in <productname>PostgreSQL</productname> 8.1, indexes can be
used either directly or via <quote>bitmap scans</>. In a bitmap scan
the output of several indexes can be combined via AND or OR rules;
- so it is difficult to associate individual heap row fetches
+ so it is difficult to associate individual heap row fetches
with specific indexes when a bitmap scan is used. Therefore, a bitmap
scan increments the
<structname>pg_stat_all_indexes</>.<structfield>idx_tup_read</>
<entry>
Returns a record of information about the backend with the specified pid, or
one record for each active backend in the system if <symbol>NULL</symbol> is
- specified. The fields returned are the same as in the
+ specified. The fields returned are a subset of those in the
<structname>pg_stat_activity</structname> view.
</entry>
</row>