Author: mreutegg
Date: Mon Jan 30 15:16:44 2017
New Revision: 1780922
URL: http://svn.apache.org/viewvc?rev=1780922&view=rev
Log:
OAK-4030: DocumentNodeStore: required server time accuracy
Modified:
jackrabbit/oak/trunk/oak-doc/src/site/markdown/nodestore/documentmk.md
Modified: jackrabbit/oak/trunk/oak-doc/src/site/markdown/nodestore/documentmk.md
URL:
http://svn.apache.org/viewvc/jackrabbit/oak/trunk/oak-doc/src/site/markdown/nodestore/documentmk.md?rev=1780922&r1=1780921&r2=1780922&view=diff
==============================================================================
--- jackrabbit/oak/trunk/oak-doc/src/site/markdown/nodestore/documentmk.md
(original)
+++ jackrabbit/oak/trunk/oak-doc/src/site/markdown/nodestore/documentmk.md Mon
Jan 30 15:16:44 2017
@@ -181,6 +181,21 @@ As seen in the examples above, a revisio
* A counter to distinguish revisions created with the same timestamp: `-2`
* The cluster node id where this revision was created: `-1`
+Clock requirements
+------------------
+
+Revisions are used by the DocumentMK to identify the sequence of changes done
+on items in the repository. This is also done across cluster nodes for
revisions
+with different cluster node ids. This requires the system clocks on the
machines
+running Oak and the backend system to approximately in sync. It is recommended
+to run an NTP daemon or some similar service to keep the clock synchronized.
+Oak allows clock differences up to 2 seconds between the machine where Oak is
+running and the machine where the backend store (MongoDB or RDBMS) is running.
+Oak may refuse to start if it detects a larger clock difference. Clock
+differences between the machines running in an Oak cluster will result in
+delayed propagation of changes between cluster nodes and warnings in the log
+files.
+
Branches
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