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From:Michael Widenius Date:June 29 1999 5:56pm
Subject:Re: to much fragmentation
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>>>>> "Ed" == Ed Carp <erc@stripped> writes:

>> Yes. MySQL 3.22 will fragment rows if you mix a lot of deletes/inserts into 
>> the same table.
>> 
>> The new ISAM in MySQL 3.23 will automaticly join adjacent deleted
>> blocks and can extend blocks much better than the old ISAM.

Ed> Is this why MySQL 3.22.21 eats up all my CPU when searching a 50K row
Ed> indexed table?  Almost no deletes, but lots and lots of adds.  Is there
Ed> something I can do about the CPU utilization?

If you don't have any deletes and updates, the table should not be
that fragmented.

You can check this by doing 'isamchk -dv table_name'
(You don't have to take down mysqld for this)

Why do you think MySQL is CPU and not disk bound in the above case?

Ed> By the way, I've been attending to police duties the last couple of
Ed> months, and haven't been active on the list, but will be more active in
Ed> the future :)

ok, you are forgiven :)

Regards,
Monty
Thread
to much fragmentationDavid Johnson26 Jun
  • Re: to much fragmentationSasha Pachev27 Jun
  • Re: to much fragmentationScott Hess28 Jun
    • Re: to much fragmentationVivek Khera28 Jun
    • Re: to much fragmentationMichael Widenius29 Jun
      • Re: to much fragmentationEd Carp29 Jun
        • Re: to much fragmentationSasha Pachev29 Jun
        • Re: to much fragmentationMichael Widenius29 Jun
          • Authentication methodsRoger Smith29 Jun
            • Authentication methodsJani Tolonen1 Jul
        • Re: to much fragmentationScott Hess29 Jun
      • Re: to much fragmentationEd Carp29 Jun
        • Re: to much fragmentationMichael Widenius30 Jun
      • Re: to much fragmentationT├Ánu Samuel29 Jun
  • Re: to much fragmentationScott Hess28 Jun
Re: to much fragmentationFred Lindberg28 Jun