php / php/php-src

Resource ID space overflow: Better approach to incremental resource id assignment

Abierto
#19,253 3 comentarios 0 reacciones 0 asignados Ver en GitHub

Nadie ha tomado este issue todavía.

Bug Status: Needs Triage
Lenguaje dominante
C
Estrellas
40.4k
Forks
8.1k
Merge medio
2 d 13 h
PR fusionados (30 d)
96

Descripción

Description

We have the following simple code that runs in a daemon which is expected to to run very long time. However it looks like a new resource id is assigned every time this runs. And this runs a lot as we write to a ramdisk.
The following code:

61
62 file_put_contents("/dev/shm/somefile.txt", $data, LOCK_EX);
63 

Resulted in this output:

PHP Fatal error:  Resource ID space overflow in cache.class.php on line 62

But I expected this output instead:

No errors.
I understand that file_put_contents() creates a temporary file resource on each run and probably it's reaching  PHP_INT_MAX to cause this fatal error.
There is only one function get_resource_id() to guess and deal with this issue. Workaround is to keep file handles active during execution.

A)
PHP can handle this by resetting it back to 0 and adding a check to compare it to existing active resources(to avoid conflict) If this is not feasible, I could propose following:
1) In addition to get_resource_id(), we need **get_all_resource_ids**() : Return all active variables with resource ids
2) **resource_id_update**(existing, new) to move active variables to a specific range,
3) **resource_id_range** (0, PHP_INT_MAX) : This would reset back to start when max is reached.

With these extra methods, long running processes can allocate their active resources to a range and let dynamic resource id allocation out of conflict.

B) Another simpler approach could be: Assuming program creates all permanent resources for that run session after a few seconds, program can call a new method: resource_set_dynamic(). This method should record current+1 resource id in memory as "start point" and whenever overflow is due, it can reset it back to start point. This would avoid conflict with permanent resources which would be already created.

C) Checking against existing IDs could be another approach but this may have some impact on performance.
PHP Version
PHP 8.2.7 (cli) (built: Jul 20 2023 18:02:54) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.2.7, Copyright (c) Zend Technologies
    with Zend OPcache v8.2.7, Copyright (c), by Zend Technologies
Operating System

Debian 12.11

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Línea de trabajo

Reproduzca el caso del daemon de larga duración de cache.class.php, línea 62, usando file_put_contents() en /dev/shm con PHP 8.2.7 CLI; después, siga la asignación de resource-ID a la que llega ese punto de entrada. El issue presenta varias estrategias de asignación en competencia, pero no define qué comportamiento o prueba debería establecer la finalización.

Escrito por el modelo de indexación a partir del texto del issue.

Evaluación

Stack tecnológico
php
Área
backend
Tipo de issue
Error
Dificultad
5/5
Tiempo estimado
Más de una semana
Estado de actividad
Estancado
Claridad
Necesita aclaración
Aptitud para principiantes
25/100

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