Laravel jobs concurrency untangling

jobs_copy.sql

DROP TABLE IF EXISTS jobs_copy;
CREATE TABLE `jobs_copy` (   `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,   `queue` varchar(255) COLLATE utf8_unicode_ci NOT NULL,   `payload` text COLLATE utf8_unicode_ci NOT NULL,   `attempts` tinyint(3) unsigned NOT NULL,   `reserved` tinyint(3) unsigned NOT NULL,   `reserved_at` int(10) unsigned DEFAULT NULL,   `available_at` int(10) unsigned NOT NULL,   `created_at` int(10) unsigned NOT NULL,   PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=29972441 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
INSERT INTO `jobs_copy` SELECT * FROM `jobs`;
DELETE FROM jobs WHERE `reserved` != 1 AND `id` IN (SELECT `id` FROM jobs_copy ORDER BY `id` DESC);
# Repeat ad nauseam: 
INSERT INTO `jobs` (SELECT * FROM `jobs_copy` ORDER BY `id` ASC LIMIT 500); DELETE FROM `jobs_copy` ORDER BY `id` ASC LIMIT 500; SELECT SLEEP(18);  SELECT COUNT(*) FROM `jobs`;