I recently got this email from a reader on my site and since I haven't posted for a while, I thought it might be a good discussion:

Jay,

I've been reading your site and had a question that you might have good insight for.  

I'm working on a high-traffic website that includes forums.  All the code is custom PHP, including the forums, simply because the PHP BB software out there doesn't scale as large and as well as I wanted.  I've implemented heavy memcached usage, distributed databases, etc. to handle any level of growth we may hit.

I spent some time going through the source the other day in order to try to understand the difference between these SHOW STATUS variables in 5.x:

I haven't gotten any responses to my question from Friday, so I figured I'd post a more direct question:

As a follow up to the series of posts I've been making, I wanted to post what I ended up with.  Thanks to everyone who posted comments, your help was extremely useful. To recap, I have a working pair of events to add and remove partitions to this table:

create table log (
    logged datetime not null,
    id int not null auto_increment,
    text varchar(256),
    PRIMARY KEY ( logged, id )
)
PARTITION BY RANGE( TO_DAYS( logged ) ) (
    PARTITION p20080206 VALUES LESS THAN (733444),
    PARTITION p20080207 VALUES LESS THAN (733445),
    PARTITION p20080208 VALUES LESS THAN (733446)

I created my Events to handle adding new partitions (and removing old ones) from my log table and they seem to be working.  However, today I noticed that the events ran a few hours later than they ran yesterday.  

          EVENT_TYPE: RECURRING
          EXECUTE_AT: NULL
      INTERVAL_VALUE: 1
      INTERVAL_FIELD: DAY
            SQL_MODE: 
              STARTS: 2008-02-13 05:36:21
                ENDS: NULL
              STATUS: ENABLED
       ON_COMPLETION: NOT PRESERVE
             CREATED: 2008-02-13 05:36:21
        LAST_ALTERED: 2008-02-13 05:36:21
       LAST_EXECUTED: 2008-02-14 07:32:22