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Revisions to docs per Steve's comments

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commit 72ed0337641eefda095cfcb706562d71d9c03413 1 parent c6082bc
authored March 14, 2011
19  doc/adminguide/monitoring.sgml
@@ -528,23 +528,12 @@ becoming a repetitive recursive activity.</para></listitem>
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 <listitem><para> Timestamps are based on the clock time of the &lslon;
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 process.</para>
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-<para> It might seem somewhat desirable for the database to record
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-DB-centred timestamps, unfortunately that would only be the correct
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-time if each thread were responsible for stowing its own activities in
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-&slcomponents; in the database.  This would multiply database
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-activity, and the implementation instead passes requests to a single
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-thread that uses a single DB connection to record things, with the
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-consequence that timestamps must be captured based on the system clock
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-of the &lslon; process. </para>
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-
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 <para> In order for the timestamps to be accurate, it is important to
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 use NTP or similar technology to keep servers' clocks synchronized, as
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-recommended in <xref linkend="requirements">.</para>
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-
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-<para> If the host where a &lslon; runs has its time significantly out
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-of sync with the database that it manages, queries against
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-&slcomponents; may provide results that will confuse the
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-reader.</para>
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+recommended in <xref linkend="requirements">.  If the host where a
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+&lslon; runs has its time significantly out of sync with the database
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+that it manages, queries against &slcomponents; may provide results
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+that will confuse the reader.</para>
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 </listitem>
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 <listitem><para> process.</para> </listitem>
7  doc/adminguide/prerequisites.sgml
@@ -42,8 +42,15 @@ timestamps sourced from multiple servers.</para></listitem>
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 <listitem><para>Monitoring table &slcomponents; captures timestamps
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 based on the clock time on the host running &lslon;.</para></listitem>
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+<listitem><para> &lslon; logs are likely to contain
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+timestamps.</para></listitem>
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+
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 </itemizedlist>
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+<para> Figuring out what is going on is likely to be made rather
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+confusing if the database servers and servers where &lslon; instances
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+run do not agree on what time it its. </para>
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+
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 </listitem>
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 <listitem><para>A reliable network between nodes</para>
14  src/slon/monitor_thread.c
@@ -5,8 +5,6 @@
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  *
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  *	Copyright (c) 2011, PostgreSQL Global Development Group
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  *	Author: Christopher Browne, Afilias Canada
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- *
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- *
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  *-------------------------------------------------------------------------
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  */
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@@ -43,7 +41,7 @@ int			monitor_interval;
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 /* ----------
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  * slon_localMonitorThread
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  *
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- * Monitoring thread that periodically flushes stackd-up monitoring requests to database
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+ * Monitoring thread that periodically flushes stacked-up monitoring requests to database
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  * ----------
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  */
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 void *
@@ -307,6 +305,16 @@ monitor_state(char *actor, int node, pid_t conn_pid, /* @null@ */ char *activity
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 	tos->node = node;
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 	tos->conn_pid = conn_pid;
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 	tos->event = event;
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+
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+/* It might seem somewhat desirable for the database to record
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+ *  DB-centred timestamps, unfortunately that would only be the
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+ *  correct time if each thread were responsible for stowing its own
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+ *  activities in sl_components in the database.  This would multiply
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+ *  database activity, and the implementation instead passes requests
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+ *  to a single thread that uses a single DB connection to record
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+ *  things, with the consequence that timestamps must be captured
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+ *  based on the system clock of the slon process. */
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+
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 	tos->start_time = time(NULL);
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 	if (actor != NULL)
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 	{

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