Re: Libpq support to connect to standby server as priority - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Libpq support to connect to standby server as priority
Date
Msg-id 26890.1542047012@sss.pgh.pa.us
Whole thread Raw
In response to Re: Libpq support to connect to standby server as priority  (Laurenz Albe <laurenz.albe@cybertec.at>)
Responses Re: Libpq support to connect to standby server as priority
List pgsql-hackers
Laurenz Albe <laurenz.albe@cybertec.at> writes:
> Haribabu Kommi wrote:
>> Added comments along the lines that you mentioned. And also try
>> to update some more comments.

> Looks ok to me, I'll mark it as "ready for committer".

I don't like this patch at all: the business with keeping two connections
open seems impossibly fragile and full of race conditions.  (For instance,
by the time you return the read-only session to the application, it might
not be read-only any more.  I also wonder what inquiry functions like
PQsocket ought to return while in this state.)  I think the feature
definition needs to be re-thought to make that unnecessary.

Also, we really need to consider the interaction between this and the
feature(s) being discussed in the thread at

https://www.postgresql.org/message-id/flat/1700970.cRWpxnom9y%40hammer.magicstack.net

            regards, tom lane


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