Bug #40722 Key Buffer Size May Not Be Optimal For System RAM needs tweaking
Submitted: 13 Nov 2008 23:08 Modified: 2 Dec 2008 3:42
Reporter: Mark Leith Email Updates:
Status: Closed Impact on me:
Category:MySQL Enterprise Monitor: Advisors/Rules Severity:S3 (Non-critical)
Version:2.0 OS:Any
Assigned to: Andy Bang CPU Architecture:Any

[13 Nov 2008 23:08] Mark Leith
Key Buffer Size May Not Be Optimal For System RAM says:

"You cannot set the buffer > 4Gb"

However, you can now in certain circumstances, as detailed within the "Key Buffer Size Greater Than 4 GB" advisor:

"However, prior to MySQL version 5.0.52 this key buffer is limited in size to 4 GB, even on 64-bit operating systems. If set to a larger value, mysqld may crash when it tries to increase the actual buffer beyond 4 GB. Note that key_buffer_size is limited to 4GB on both 32-bit and 64-bit Windows systems, even in MySQL version 5.0.52 and later."

How to repeat:

Suggested fix:
Change "You cannot set the buffer > 4Gb" to:

You cannot set the buffer > 4Gb, on versions less than 5.0.52, or any Windows version
[17 Nov 2008 23:34] Andy Bang
Pushed up to revision 240.
[2 Dec 2008 3:42] Bill Weber
verified changed in advisor bundle