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Thread: Warning for exceeding max locks?

Warning for exceeding max locks?

From
"Joshua D. Drake"
Date:
Hello,

We ran into a problem with a customer this weekend. They had >128,000 
tables and we were trying to run a pg_dump. When we reached 
max_locks_per_transaction, the dump just hung waiting to lock the next 
table.

Would it make sense to have some sort of timeout for that?

wait_for_lock_timeout?

Joshua D. Drake

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Re: Warning for exceeding max locks?

From
Tom Lane
Date:
"Joshua D. Drake" <jd@commandprompt.com> writes:
> We ran into a problem with a customer this weekend. They had >128,000 
> tables and we were trying to run a pg_dump. When we reached 
> max_locks_per_transaction, the dump just hung waiting to lock the next 
> table.

> Would it make sense to have some sort of timeout for that?

I don't think you have diagnosed this correctly.  Running out of lock
table slots generates an "out of shared memory" error, with a HINT that
you might want to increase max_locks_per_transaction.  If you can prove
otherwise, please supply a test case.
        regards, tom lane

Re: Warning for exceeding max locks?

From
"Joshua D. Drake"
Date:
Tom Lane wrote:
> "Joshua D. Drake" <jd@commandprompt.com> writes:
>> We ran into a problem with a customer this weekend. They had >128,000 
>> tables and we were trying to run a pg_dump. When we reached 
>> max_locks_per_transaction, the dump just hung waiting to lock the next 
>> table.
> 
>> Would it make sense to have some sort of timeout for that?
> 
> I don't think you have diagnosed this correctly.  Running out of lock
> table slots generates an "out of shared memory" error, with a HINT that
> you might want to increase max_locks_per_transaction.  If you can prove
> otherwise, please supply a test case.

You are correct, I didn't have all the information from my team members. 
Not that it should surprise you that you are correct ;)

Thanks for replying.

Joshua D. Drake


> 
>             regards, tom lane
> 


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      === The PostgreSQL Company: Command Prompt, Inc. ===
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