| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at> |
| Cc: | Haribabu Kommi <kommi(dot)haribabu(at)gmail(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, Jing Wang <jingwangian(at)gmail(dot)com>, Pg Hackers <pgsql-hackers(at)postgresql(dot)org>, "Tsunakawa, Takayuki" <tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com> |
| Subject: | Re: Libpq support to connect to standby server as priority |
| Date: | 2018-11-12 18:23:32 |
| Message-ID: | 26890.1542047012@sss.pgh.pa.us |
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| Lists: | pgsql-hackers |
Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)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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