Re: Performance tuning Oracle Context

In article <36655e19.33253676_at_newshost.us.oracle.com>,   jkallman_at_us.oracle.com (Joel R. Kallman) wrote:
> On Tue, 01 Dec 1998 18:54:39 GMT, rbelanger_at_forrester.com wrote:
>
> >Hello:
> >
> >We are working on a Context application that indexes about 1,000 large
> >documents (15-18 pages) and about 10,000 small documents (2-3 pages).
> >
> >Indexing performance seems to be pretty good, but retrieval performance is
> >only OK. We are using two-step queries and the average query is taking about
> >10 seconds. I would like to get it down to about 2-3 seconds.
>
> What types of queries are you performing? Single-word/phrase? Text
> and structured? Fuzzy? There can be performance differences due to
> the nature of each of these types of queries.

Mostly single-word/phrase but we are also including a structured clause.

> >
> >The database server is a Sun Enterprise 3500 with 512 Mb of memory, with
> >about a 320 Mb buffer cache, 60 Mb shared pool. We also have SORT_MEMORY
> >SIZE turned up to about 8M to keep most sorts in memory. The datafiles are
> >on an EMC Symmetrix and are distributed across a series of mirrored
> >partitions.
> >
> >During searches we see a fairly high IO load on the EMC, with almost no CPU
> >utilization.
>
> The easiest way to solve this would be to turn on TIMED_STATISTICS in
> your database and trace the ConText session. I solved a customer's
> "problem" with ConText by doing exactly this...tracing the ConText
> session. In fact, the 2-step query was performing very fast (under 1
> second), but then the resultant non-indexed join they were doing with
> the result table caused a full-table scan...and hence, degraded
> performance.

Good idea. I will take a look at this.

> >
> >We have tuned our engine preferences to create large tables for the Context
> >index tables to prevent chaining and fragmentation.
> >
> >Any ideas on tuning approaches for Context would be appreciated.
> >
> >-----------== Posted via Deja News, The Discussion Network ==----------
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>
> Thanks!
>
> Joel
>
> Joel R. Kallman
> Oracle Government, Education, & Health
> Columbus, OH http://govt.us.oracle.com
> jkallman@us.oracle.com http://www.oracle.com
>
> ----
> The statements and opinions expressed here are my own
> and do not necessarily represent those of Oracle Corporation.
>

-----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own Received on Wed Dec 02 1998 - 18:40:17 CST