[rt-users] RT query for test InnoDB performance

[Vivek Khera]

On Jan 16, 2006, at 9:56 AM, Goddard Lee wrote:

>>> Since few months, i perceive a sensible performance
>> degradation. Mysql
>>> Support suggest me to do an "ALTER TABLE table
>> ENGINE=InnoDB;" (Null
>>> alter table) to defragment the table and recalculate index
>> statistics.
>>
>> RT should _alway_ be run with InnoDB tables if you're running
>> on MySQL. Running with the default "MyISAM" table type is
>> dangerous and should be avoided.
>
> I think he meant that MySQL support suggested he do that to force  
> MySQL
> to sort itself out, not to actually change the table type.

My understanding is that the above ALTER command does the moral  
equivalent of a VACUUM FULL in postgres.  ie, it cleans out the dead  
tuples and reclaims the unused space from the table.

It is a travesty that there is no normal way to do that other then  
incurring downtime in mysql.