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From:Michael Widenius Date:October 14 1999 1:01am
Subject:Re: MySQL not increasing buffers
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>>>>> "Bob" == Bob Kline <bkline@stripped> writes:

Bob> On Wed, 13 Oct 1999 sinisa@stripped wrote:
>> 
>> It does. Oldest get's out. The one that has spent most of the time,
>> and not being used is thrown out to make space for the new one.
>> 
>> The newest one has no chance of being thrown out with a next entry.
>> 
>> That is FILO. It is similar to LRU.
>> 

Bob> Definition:
   
Bob>     first-in last-out (FILO): A queuing discipline in which entities in
Bob>     a queue leave the queue in the reverse order from that in which they
Bob>     arrived.

Bob> This means that if you have a queue with three elements A, B, and C, for
Bob> which A arrived first, B arrived second, and C arrived third, the items
Bob> will leave the queue in the order C, B, A.  For a cache this means that
Bob> you are discarding C first, instead of A, which is the least-recently
Bob> used (LRU).  For a DBMS (such as MySQL) this is almost always a less
Bob> useful approach than one in which the least-recently used keys are
Bob> discarded first when the cache needs to free up some space.

Bob> Does this help?

Hi!

The MySQL key cache isn't a strict queue as keys may be reordered if
you hit a row that is already in the queue.  The method is strictly
'oldest accessed key_buffer gets out'.

Regards,
Monty
Thread
MySQL not increasing buffersThomas van Gulick12 Oct
  • Re: MySQL not increasing bufferssinisa12 Oct
  • Re: MySQL not increasing buffersThomas van Gulick12 Oct
    • Re: MySQL not increasing bufferssinisa13 Oct
      • Re: MySQL not increasing buffersBob Kline13 Oct
        • Re: MySQL not increasing bufferssinisa13 Oct
          • Re: MySQL not increasing buffersBob Kline13 Oct
            • Re: MySQL not increasing bufferssinisa13 Oct
              • Re: MySQL not increasing buffersBob Kline13 Oct
                • Re: MySQL not increasing buffersMichael Widenius14 Oct
                  • Re: MySQL not increasing buffersBob Kline14 Oct
                  • Re: MySQL not increasing buffersVivek Khera15 Oct
              • Re: MySQL not increasing buffersJules Bean15 Oct
  • MySQL not increasing buffersMichael Widenius13 Oct
RE: MySQL not increasing buffersBob Kline15 Oct
Re: MySQL not increasing buffersBob Kline15 Oct
RE: MySQL not increasing buffersbkline15 Oct