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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"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

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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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