[oslc-core] TRS truncation of change log

[Joe Ross]

The Tracked Resource Set specification, states the following:

   "To ensure that a new Client can always get started, the Change Log MUST
   contain the base cutoff event of the corresponding Base, and all Change
   Events more recent than it. Thus the Server is only allowed to truncate
   Change Events older than the base cutoff event. "

However, since processing of the change log would happen some time after
the base was read, it is possible that truncation happens between the time
that a client reads the base and the time that it starts processing the
change log. Truncation could also happen while a client is paging through
the change log. In that case, it would be useful for a client to know about
the truncation event before processing the entire change log, so that it
can switch gears and obtain a new base snapshot instead. It seems that it
might be useful if each page of the change log also included a lastEvent
property. If at some point during change log processing, lastEvent becomes
more recent than the cutoffEvent value that client knows, the client could
then abandon change log processing and obtain a new base snapshot instead.

Of course, we can add this property in our implementation, but seems it
might be useful as an addition to the spec.


================================================
Joe Ross/Austin/IBM, joeross at us.ibm.com
Tivoli Autonomic Computing & Component Technologies
512-286-8311, T/L 363-8311
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://open-services.net/pipermail/oslc-core_open-services.net/attachments/20130502/95d8fb70/attachment.html>