Bug #20988 Query cache size is limited to unsigned int size (2 gb)

• Submitted: 12 Jul 2006 9:13
• Modified: 26 Jan 2009 14:18
• Reporter: Oli Sennhauser
• Status: Duplicate
• Category: MySQL Server: Query Cache
• Severity: S4 (Feature request)
• Version: 5.0.21
• OS: Any
• CPU Architecture: Any
• Tags: 2 gb, cache, limit, query, size

[12 Jul 2006 9:13] Oli Sennhauser

Description:
When Query cache size is set above 2 gb (yes i know it is to huge). It is set back to 0 (does it mean query cache is disabled then?). This is IMHO not appropriate in 64bit world anymore!

How to repeat:
mysql> show global variables like 'query_cache_size%';
+------------------+-----------+
| Variable_name    | Value     |
+------------------+-----------+
| query_cache_size | 536870912 |
+------------------+-----------+

mysql> set global query_cache_size=3*1024*1024*1024;

mysql> show global variables like 'query_cache_size%';
+------------------+-------+
| Variable_name    | Value |
+------------------+-------+
| query_cache_size | 0     |
+------------------+-------+

mysql> set global query_cache_size=512*1024*1024;

mysql> show global variables like 'query_cache_size%';
+------------------+-----------+
| Variable_name    | Value     |
+------------------+-----------+
| query_cache_size | 536870912 |
+------------------+-----------+

Suggested fix:
I generally recommend to use bigints for all suche size metrics (also for the future). We will always run into the same troubles. And 64bit world started since long time ago!

[14 Jul 2006 10:43] Valeriy Kravchuk

Thank you for a reasonable feature request.

[26 Jan 2009 14:03] Mattias Jonsson

Bug#22239 is related.

[26 Jan 2009 14:18] Mattias Jonsson

Duplicate of bug#32213