[rt-users] RT query for test InnoDB performance

[Ruslan Zakirov]

On 1/18/06, Vivek Khera <vivek at khera.org> wrote:
>
> 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's not full vacuum, it only rebuilds indexes.

>
> It is a travesty that there is no normal way to do that other then
> incurring downtime in mysql.
Really, to get full vacuum on InnoDB you have to use dump&restore, this's sad.

--
Best regards, Ruslan.