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From Knut Anders Hatlen <Knut.Hat...@Sun.COM>
Subject Re: Should we investigate increasing the QRYDTA block size?
Date Sat, 11 Feb 2006 21:47:43 GMT
Bryan Pendleton <bpendleton@amberpoint.com> writes:

> I was studying the work that Knut Anders has been doing on
> DERBY-821 and DERBY-822, and I came across the following
> statement in the DRDA spec (Volume 1, page 12):
>    Blocking applies only to the QRYDTA reply objects. Each
>    query block is a QRYDTA DSS. The maximum query block size
>    value allowed in the qryblksz parameter is increased from
>    32K to 10M, thus accomodating the larger data volumes
>    required by modern, more data-intensive applications.
> Is this idea already on the radar of the folks looking at
> Network Server performance issues? If not, should we add it
> to the list of ideas to pursue?

I wasn't aware the block size could be greater than 32K, so it wasn't
on my radar at least. The transactions I have been looking at are
single-record selects, and they are not influenced by the block size.

I guess the ideal block size is hard to find and depends on the type
of application you are running. Maybe LOBs would benefit from larger
block size?

> I tried searching JIRA to see if this was already logged, but
> it's still being a tad cranky today, so pardon me if you've
> already logged this one.

It's probably a good idea to file it in JIRA so that it is not

Knut Anders

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