locked
useSequencing configuration in rtsearchrc.xml RRS feed

  • Question

  • Can anyone provide additional information about the useSequencing variable in rtsearchrc.xml?

    I believe that FAST ESP 5.3 uses it to keep updates straight when it is set to "true". However, feeding throughput is much faster when it is set to "false".

    Is this variable used when updating metadata on a previously fed document? I can't seem to find many details in the FAST ESP 5.3 documentation explaining its use.

    Wednesday, July 20, 2011 1:54 AM

Answers

  • When usesequencing="false", the indexer executes whatever it gets, in the order it gets it.  This might be in a different order than originally sent to FAST. If sequencing is enabled, operation order is restored.  This applies to any type of operation, be an add/update/partial update/deletes.  Sequencing order is required if using indexer fault tolerance, or FeedingProxy with consistent failover.

    What to choose depends on how important the feeding order is.  If updates to a document are always "far apart" in time, maybe days, then you may be able to turn off the usesequencing.  However, if documents and subsequent updates are close together in time, you have to leave sequencing on to ensure that they are indexed in the right order.

    I've heard of custom feeding solutions where the content feeder tracks the document outside of FAST, setting sequencing to false and then blocks any updates to the document until feedback has been received.

    • Marked as answer by Churchill729 Wednesday, July 20, 2011 11:29 PM
    Wednesday, July 20, 2011 7:25 PM

All replies

  • When usesequencing="false", the indexer executes whatever it gets, in the order it gets it.  This might be in a different order than originally sent to FAST. If sequencing is enabled, operation order is restored.  This applies to any type of operation, be an add/update/partial update/deletes.  Sequencing order is required if using indexer fault tolerance, or FeedingProxy with consistent failover.

    What to choose depends on how important the feeding order is.  If updates to a document are always "far apart" in time, maybe days, then you may be able to turn off the usesequencing.  However, if documents and subsequent updates are close together in time, you have to leave sequencing on to ensure that they are indexed in the right order.

    I've heard of custom feeding solutions where the content feeder tracks the document outside of FAST, setting sequencing to false and then blocks any updates to the document until feedback has been received.

    • Marked as answer by Churchill729 Wednesday, July 20, 2011 11:29 PM
    Wednesday, July 20, 2011 7:25 PM
  • Thank you for the clear and concise answer.
    Wednesday, July 20, 2011 11:29 PM