[DERBY-959] Allow use of DRDA QRYDTA block sizes greater than 32K

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 10.1.1.0, 10.1.2.1, 10.2.1.6
• Fix Version/s: 10.2.1.6
• Component/s: Network Client, Network Server
• Bug behavior facts: Performance
• Assignee: Sunitha Kambhampati
• Reporter: Bryan Pendleton
• Created: 12/Feb/06 11:39
• Updated: 29/Jun/09 14:37
• Resolved: 06/Jul/06 04:38

Description

Currently, the Network Server and Network Client use a 32K blocksize when
returning database data in QRYDTA blocks.

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.

The importance of larger block sizes depends strong on the application
profile.. For example, many applications perform single-record selects,
and they are not influenced by the block size.

But for some applications, it seems like the ability to use a larger block
size could be quite valuable.

Issue Links

• is related to: DERBY-1441 Allow client to be able to send greater than 32k query block size.
• is related to: DERBY-1442 Do performance analysis and come up with a good query block size value for the client to send to the server