On Thu, Jun 15, 2017 at 2:16 PM, Andres Freund <and...@anarazel.de> wrote: > On 2017-06-14 11:48:25 +0300, Marina Polyakova wrote:
>> I suggest a patch where pgbench client sessions are not disconnected because >> of serialization or deadlock failures and these failures are mentioned in >> reports. > > I think that's a good idea and sorely needed. +1 >> P.S. Does this use case (do not retry transaction with serialization or >> deadlock failure) is most interesting or failed transactions should be >> retried (and how much times if there seems to be no hope of success...)? > > I can't quite parse that sentence, could you restate? The way I read it was that the most interesting solution would retry a transaction from the beginning on a serialization failure or deadlock failure. Most people who use serializable transactions (at least in my experience) run though a framework that does that automatically, regardless of what client code initiated the transaction. These retries are generally hidden from the client code -- it just looks like the transaction took a bit longer. Sometimes people will have a limit on the number of retries. I never used such a limit and never had a problem, because our implementation of serializable transactions will not throw a serialization failure error until one of the transactions involved in causing it has successfully committed -- meaning that the retry can only hit this again on a *new* set of transactions. Essentially, the transaction should only count toward the TPS rate when it eventually completes without a serialization failure. Marina, did I understand you correctly? -- Kevin Grittner VMware vCenter Server https://www.vmware.com/ -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
