On Tue, Nov 21, 2006 at 09:31:21AM +0100, Sergei Golubchik wrote:
> Hi!
>
> On Nov 21, Marko M?kel? wrote:
> > I have been informed that in MySQL 5.1, pluggable storage engines will be
> > able to declare their own configuration parameters and settable variables.
> > In struct st_mysql_plugin (include/mysql/plugin.h), there are three
> > fields for this:
> >
> > struct st_mysql_show_var *status_vars;
> > void * __reserved1; /* placeholder for system variables */
> > void * __reserved2; /* placeholder for config options */
> >
> > I would have expected to find an example of the usage in
> > storage/example/ha_example.cc. Alas, all three fields are initialized
> > to NULL there, just like in every other storage engine that is currently
> > available at bk://mysql.bkbits.net/mysql-5.1.
>
> This is not implemented yet :(
>
> > When will this be implemented?
>
> This is work in progress, Antony is working on it at the very moment.
Thanks, Sergei. Is there any new ETA? I was told that it should be
completed by the end of September (which I assumed to be September 2006).
> > I hope that the __reserved1 and __reserved2 will be function pointers,
> > because that would allow the storage engine to be notified when a
> > change is requested. That kind of functionality would be desired for
> > resizing the InnoDB buffer pool at runtime.
>
> Sure, it will be possible.
Excellent! For resizing the buffer pool, it would be nice if the client
blocked until the buffer pool has been resized. Enlarging it should be
fast, but shrinking can take some time if the database is under heavy
load.
Marko
