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Re: InnoDB: Warning: a long semaphore wait:. X-lock on RW-latch
Posted by: Rick James
Date: December 27, 2008 07:41PM

SET timestamp is a way to get a predictable NOW(). The slow query follows it.

Is the index on orders.id UNIQUE (or PRIMARY KEY)? Ditto for sessions.id? Or, at least, is there only one row with the id in question?

Did you kill any threads? I'm fishing for a JOIN between one of these tables and some other table, such that there is an index missing somewhere and it tied up all the rows, thereby blocking the UPDATE. But then it is puzzling that the SELECT would be blocked for 7 minutes.

Sorry, I don't have a quick answer.

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Re: InnoDB: Warning: a long semaphore wait:. X-lock on RW-latch
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December 27, 2008 07:41PM


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