Re: [HACKERS] SERIALIZABLE with parallel query

On Fri, Mar 30, 2018 at 2:56 PM, Thomas Munro
<thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> On Thu, Mar 8, 2018 at 10:28 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> +SerializableXactHandle
>> +ShareSerializableXact(void)
>> +{
>> + Assert(!IsParallelWorker());
>> +
>> + return MySerializableXact;
>> +}
>>
>> Uh, how's that OK? There's no rule that you can't create a
>> ParallelContext in a worker. Parallel query currently doesn't, so it
>> probably won't happen, but burying an assertion to that effect in the
>> predicate locking code doesn't seem nice.
>
> Hmm. I suppose you could have a PARALLEL SAFE function that itself
> launches parallel workers explicitly (not via parallel query), and
> they should inherit the same SERIALIZABLEXACT from their parent and
> that should all just work.
>
>> Is "sxact" really the best (i.e. clearest) name we can come up with
>> for the lock tranche?
>
> Yeah, needs a better name.
>
> I have some lingering uncertainty about this patch and we're out of
> time, so I moved it to PG12 CF1. Thanks Haribabu, Robert, Amit for
> the reviews and comments so far.
>

I'd like to test and review this patches but they seem to conflict
with current HEAD. Could you please rebase them?

Regards,

--
Masahiko Sawada
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center