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From:Dan Nelson Date:May 15 2007 5:05pm
Subject:Re: Issue with locking and INSERT DELAYED
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In the last episode (May 15), Dan Buettner said:
>  Hi Edoardo -
> 
>  I think you've been misinformed; MyISAM tables do not support
>  simultaneous read and write operations.  MyISAM is a multiple
>  reader/single writer, table locking design.  You may want to switch
>  to InnoDB tables for that functionality.

MyISAM tables do allow concurrent inserts and selects, by appending the
newly-inserted records to the end of the table:

  http://dev.mysql.com/doc/refman/5.0/en/concurrent-inserts.html

Some things to try would be setting concurrent_insert=2 (to force
concurrent inserts even if there are holes in the table) or setting
low_priority_updates=1 ( to keep inserts from trying to lock the table
when there are pending selects ).  If those don't help, then you may be
forced to switch to InnoDB, or maybe set up replication and run your
reporting queries on the slave.

> http://dev.mysql.com/doc/refman/5.0/en/table-locking.html

-- 
	Dan Nelson
	dnelson@stripped
Thread
Issue with locking and INSERT DELAYEDEdoardo Serra15 May
  • Re: Issue with locking and INSERT DELAYEDDan Buettner15 May
    • Re: Issue with locking and INSERT DELAYEDDan Nelson15 May