Bug #21461 Long Varchars created unneeded waste in compression in Archive

• Submitted: 6 Aug 2006 1:28
• Modified: 13 Jul 2007 0:37
• Reporter: Brian Aker
• Status: Closed
• Category: MySQL Server: Archive storage engine
• Severity: S5 (Performance)
• Version: 5.0
• OS: Any (all)
• Assigned to: Brian Aker
• CPU Architecture: Any

[6 Aug 2006 1:28] Brian Aker

Description:
A row that is passed into write_row is not zero'ed on each call. This means that a previous rows data is still to be found there. For archive this means wasted compression on very large varchar (and worse write/read performance). 

How to repeat:
Insert a row into archive with a varchar over 255 and open up the file in a binary editor. 

Suggested fix:
Null bytes for varchar before compressing.

[13 Jul 2007 0:37] Brian Aker

Fixed this sometime ago.