Re: pgsql: psql: Add test for query canceling

> On 24 Aug 2021, at 18:43, Peter Eisentraut <peter.eisentraut@enterprisedb.com> wrote:
>
> On 20.08.21 20:47, Tom Lane wrote:
>> I think you should drop the overly-cute bit with a SIGALRM handler,
>> and instead have a loop-with-delay around an attempt to read the
>> psql.pid file, after launching the psql run without an immediate
>> wait for termination.  That gets rid of the first problem (though
>> you still want the loop to timeout eventually, it could wait up
>> to say 180 seconds, as we do elsewhere).  Then the second problem
>> is easy to solve by making the pg_sleep delay twice as much.
>
> Here is a proposal.  It waits separately for the pid file to appear and also checks for the sleep query to be
registeredby the backend, so it doesn't have any more dependencies on things happening "fast enough". And it's also
fasterin the normal case now.  Thoughts? 

From reading the patch, that looks like a really good combination of ideas for
this test.  +1.

--
Daniel Gustafsson        https://vmware.com/