Re: [HACKERS] statement_timeout is not working as expected with postgres_fdw

On Thu, May 4, 2017 at 10:18 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Thu, May 4, 2017 at 12:18 PM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>> As soon as the first command fails due to timeout, we will set
>> 'abort_cleanup_failure' which will make a toplevel transaction to
>> abort and also won't allow other statements to execute.  The patch is
>> trying to enforce a 30-second timeout after statement execution, so it
>> has to anyway wait till the command execution completes (irrespective
>> of whether the command succeeds or fail).
>
> I don't understand what you mean by this.  If the command doesn't
> finish within 30 seconds, we *don't* wait for it to finish.
>

+ /*
+ * Submit a query.  Since we don't use non-blocking mode, this also can
+ * block.  But its risk is relatively small, so we ignore that for now.
+ */
+ if (!PQsendQuery(conn, query))
+ {
+ pgfdw_report_error(WARNING, NULL, conn, false, query);
+ return false;
+ }
+
+ /* Get the result of the query. */
+ if (pgfdw_get_cleanup_result(conn, endtime, &result))
+ return false;

The 30 seconds logic is in function pgfdw_get_cleanup_result, can't
the command hang in PQsendQuery?



-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com