diff options
Diffstat (limited to 'lib/kernel/doc/src/kernel_app.xml')
| -rw-r--r-- | lib/kernel/doc/src/kernel_app.xml | 37 |
1 files changed, 22 insertions, 15 deletions
diff --git a/lib/kernel/doc/src/kernel_app.xml b/lib/kernel/doc/src/kernel_app.xml index 3914226a3e..ccb7d17d25 100644 --- a/lib/kernel/doc/src/kernel_app.xml +++ b/lib/kernel/doc/src/kernel_app.xml @@ -310,24 +310,31 @@ <tag><c>net_ticktime = TickTime</c></tag> <item> <marker id="net_ticktime"></marker> - <p>Specifies the <c>net_kernel</c> tick time. <c>TickTime</c> - is specified in seconds. Once every <c>TickTime/4</c> second, all - connected nodes are ticked (if anything else is written - to a node). If nothing is received from another node - within the last four tick times, that node is considered - to be down. This ensures that nodes that are not responding, - for reasons such as hardware errors, are considered to be - down.</p> - <p>The time <c>T</c>, in which a node that is not responding is - detected, is calculated as <c><![CDATA[MinT < T < MaxT]]></c>, where:</p> + <p>Specifies the <c>net_kernel</c> tick time in seconds. This is the + approximate time a connected node may be unresponsive until it is + considered down and thereby disconnected.</p> + <p>Once every <c>TickTime/4</c> seconds, each connected node is ticked + if nothing has been sent to it during that last <c>TickTime/4</c> + interval. A tick is a small package sent on the connection. A connected + node is considered to be down if no ticks or payload packages have been + received during the last four <c>TickTime/4</c> intervals. This ensures + that nodes that are not responding, for reasons such as hardware errors, + are considered to be down.</p> + <p>As the availability is only checked every <c>TickTime/4</c> seconds, + the actual time <c>T</c> a node have been unresponsive when + detected may vary between <c>MinT</c> and <c>MaxT</c>, + where:</p> <code type="none"> MinT = TickTime - TickTime / 4 MaxT = TickTime + TickTime / 4</code> - <p><c>TickTime</c> defaults to <c>60</c> (seconds). Thus, - <c><![CDATA[45 < T < 75]]></c> seconds.</p> - <p>Notice that <em>all</em> communicating nodes are to have the <em>same</em> - <c>TickTime</c> value specified.</p> - <p>Normally, a terminating node is detected immediately.</p> + <p><c>TickTime</c> defaults to <c>60</c> seconds. Thus, + <c><![CDATA[45 < T < 75]]></c> seconds.</p> + <p>Notice that <em>all</em> communicating nodes are to have the + <em>same</em> <c>TickTime</c> value specified, as it determines both the + frequency of outgoing ticks and the expected frequency of incominging + ticks.</p> + <p>Normally, a terminating node is detected immediately by the transport + protocol (like TCP/IP).</p> </item> <tag><c>shutdown_timeout = integer() | infinity</c></tag> <item> |