On 2017-06-06 13:07:57 -0400, Robert Haas wrote: > > We also already rely on int32 stores being atomic in other > > parts of the code, although that's between processes not between signal > > / normal path of execution. > > I don't think the issues are much different. Presumably no CPU > delivers a signal halfway through a CPU instruction, so if we can rely > on a 4 byte store being indivisible from the perspective of some other > CPU, it seems fine to also rely on that being true in the signal > handler case.
The signal handler case is the "weaker" one I think - you'll only ever see the result of an entire CPU instruction, whereas cross-cpu concurrency can allow another cpu to see state from the *middle* of an instruction if not atomic. - Andres -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers