IBM FileNet P8, Version 5.2.1            

Index server workload rebalancing

A full-text index is assigned to one IBM® Content Search Services index server at a time. This assigned server makes all index entry changes for the index. To better balance server workloads, Content Platform Engine changes the index server for an index as needed.

The following memberships determine the viable servers for a full-text index:
Site Both the server and the index area must belong to the same site. That is, suppose that a full-text index is part of an index area that belongs to site X: only servers that belong to site X can be assigned to that index.
Affinity group Both the server and the index area must belong to the same affinity group. If the index area does not belong to an affinity group, the server must also not belong to an affinity group. You can use affinity groups to dedicate index servers to particular index areas.

An index batch contains index requests for one full-text index. Before the subsystem dispatcher submits an index batch for processing, it checks the index server assignment for the full-text index in the following manner:

  1. The value of the Indexing status property is set to REBALANCING. This status change occurs only if the current value is NORMAL; if the status is not NORMAL, server reassignment does not occur.
  2. The dispatcher waits for the lease of the current index server for the full-text index to expire. The time of this expiration is indicated by the Lease expiration property for the index.
  3. The best viable index server is determined and assigned to the full-text index (if it is not already so assigned). The assigned index server is indicated by the Lease holder field for a full-text index.
  4. The value of the Indexing status property is set back to NORMAL.
The best index server for the full-text index is one of the following servers:
Non-active server If the number of possible servers is greater than the number of active full-text indexes, a currently non-active server is assigned to the index. (So each server services a maximum of one active index.)
Fastest server If the number of possible servers is less than the number of active full-text indexes, the fastest server is assigned to the index. The fastest server is the server with the lowest average processing time per index entry operation to create, update, or delete an entry. This average reflects the activity of the server since the last index assignment change for the server.


Last updated: March 2016
csscbr_workload_rebalancing.htm

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