set_time_limit() counts time while pg_get_result() waiting for asynchronous PostgreSQL query

Description

The following code:

<?php
// Connect
$conn = pg_connect("dbname='somedb'");
// Send a postgres sleep query (or anything long running query)
pg_send_query($conn, "SELECT pg_sleep(5)");
// Set PHP max execution time less than above
set_time_limit(2);
// Waiting for query to complete (but fails and error is shown)
$res = pg_get_result($conn); 
// Never printed
echo "OK";

Resulted in this output:

PHP Fatal error: maximum execution time of 2 seconds exceeded

But I expected this output instead:

OK

PHP Version

8.3.8

Operating System

Gentoo Linux

The code worked as expected in PHP 8.1, until I upgraded to PHP 8.3. I think it should not count time while the PHP script is doing nothing but waiting for the PostgreSQL server. I did not find any documentation about this change in code behaviour.

I have tried with the following cases :

last master built on ubuntu 24.04 on local pgsql server.
8.3.6 from same ubuntu with same server.
8.3.8 from macOs remote connection on this same pgsql server.

In every case I get my OK.

Thanks for the quick reply. Indeed, the code works as it should on Ubuntu, I tried it too. I have two very different Gentoo systems with PHP 8.3 and both produces the bug. I also tested PHP 8.2 on Gentoo (same configuration) and got the OK. It's weird, seems like a Gentoo specific bug on version 8.3.

As another datapoint, 8.3.8 on Windows times out as well.

I tried version 8.3.6 and 8.3.3 on Gentoo and both throws the error.

I think I found the problem, the error depends on whether thread safety is enabled or not. If I compile PHP 8.3.8 on Gentoo without threads, the above code works as should. But if I compile PHP with POSIX threads, the code breaks. On Ubuntu the PHP 8.3.6 is compiled without threads, that's why it's working okay.

does it work with ZTS and in a non async way ? e.g. just pg_query

Suprisingly, the script times out in non-async / blocking mode too:

<?php
$conn = pg_connect("host='127.0.0.1' port='5432' dbname='template1' user='postgres'");
ini_set('display_errors', '1');
// Setting execution time less than below
set_time_limit(2);
// PHP Fatal error: maximum execution time of 2 seconds exceeded
pg_query($conn, "SELECT pg_sleep(5)");
// Never printed
echo "OK";

I ll have a look in the following days.

Anybody using mysql ? If yes what happens with ZTS build with 'SELECT SLEEP(5)' query?

I tried mysqli extension with MariaDB and the PHP script times out as well. Code:

<?php
ini_set('display_errors', '1');
echo PHP_VERSION . "\n";
$conn = mysqli_connect('127.0.0.1', 'root', '1234');
// Setting execution time less than SLEEP()
set_time_limit(2);
// PHP Fatal error: maximum execution time of 2 seconds exceeded
mysqli_query($conn, "SELECT SLEEP(5)");
// Never printed
echo "OK";

Even PHP's sleep() function times out with ZTS enabled:

<?php
ini_set('display_errors', '1');
echo PHP_VERSION . "\n";
// Setting execution time less than PHP sleep()
set_time_limit(2);
// PHP Fatal error: maximum execution time of 2 seconds exceeded
sleep(5);
// Never printed
echo "OK";

Without ZTS, there is no timeout.

Ok gonna bisect it. I think that s better support Linux timeouts with ZTS part but will double-check.

@lezso6

Was wrong about the commit, @lezso6, if you build from source, can you add --enable-zend-max-execution-timers=no to the ./configure command ? I forgot about that change ..

I recompiled with ZTS enabled and Zend Max Execution Timers disabled, and the bug is gone. It works, no timeouts.

It appears on the migration guide. Distribution packagers would need to modify their build workflow to take it into account.

So if I understand correctly, this is a feature. And will be enabled for non-ZTS builds, I read that here: #6504 (comment)

Navigation Menu

Repository navigation

set_time_limit() counts time while pg_get_result() waiting for asynchronous PostgreSQL query #14769

Description

PHP Version

Operating System

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

set_time_limit() counts time while pg_get_result() waiting for asynchronous PostgreSQL query #14769

Description

Description

PHP Version

Operating System

Activity

lezso6 commented on Jul 2, 2024

devnexen commented on Jul 2, 2024

lezso6 commented on Jul 2, 2024

MorganLOCode commented on Jul 3, 2024

lezso6 commented on Jul 3, 2024

lezso6 commented on Jul 3, 2024

devnexen commented on Jul 3, 2024

lezso6 commented on Jul 3, 2024

devnexen commented on Jul 5, 2024

devnexen commented on Jul 7, 2024

lezso6 commented on Jul 7, 2024

lezso6 commented on Jul 7, 2024

devnexen commented on Jul 7, 2024

devnexen commented on Jul 7, 2024

lezso6 commented on Jul 8, 2024

devnexen commented on Jul 8, 2024

lezso6 commented on Jul 8, 2024

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions