自从我开始使用产生长调用链的 PHP 库以来，调试由它引起的问题变得越来越困难，因为我的错误日志最终包含如下输出：（某些值已使用 删除*）
2017/08/23 10:47:26 [error] 13057#13057: *206119 FastCGI sent in stderr: "PHP message: PHP Fatal error: Uncaught ActiveRecord\DatabaseException: PDOException: SQLSTATE[22P02]: Invalid text representation: 7 ERROR: invalid input syntax for integer: "" in /var/www/********/vendor/php-activerecord/php-activerecord/lib/Connection.php:337
Stack trace:
#0 /var/www/********/vendor/php-activerecord/php-activerecord/lib/Connection.php(337): PDOStatement->execute(Array)
#1 /var/www/********/vendor/php-activerecord/php-activerecord/lib/Table.php(237): ActiveRecord\Connection->query('SELECT * FROM "...', Array)
#2 /var/www/********/vendor/php-activerecord/php-activerecord/lib/Table.php(219): ActiveRecord\Table->find_by_sql('SELECT * FROM "...', Array, false, NULL)
#3 /var/www/********/vendor/php-activerecord/php-activerecord/lib/Model.php(1666): ActiveRecord\Table->find(Array)
#4 /var/www/********/vendor/php-activerecord/php-activerecord/lib/Model.php(1605): ActiveRecord\Model::find_by_pk('', Array)
#5 /var/www/********/includes/classes/Models/NSModel.php(11): ActiveRecord\Model::find(''" while reading response header from upstream, client: **.***.***.***, server: ***********, request: "POST /************************************ HTTP/1.1", upstream: "fastcgi://unix:/run/php/php7.1-fpm.sock:", host: "***********", referrer: "************************************************************"
注意最后一行 FastCGI stderr 输出在 之后突然结束ActiveRecord\Model::find(''"。另一个例子：
2017/08/22 17:20:53 [error] 13057#13057: *193907 FastCGI sent in stderr: "PHP message: PHP Fatal error: Uncaught TypeError: Argument 1 passed to App\DeviantArt::isImageAvailable() must be of the type string, null given, called in /var/www/********/includes/classes/ImageProvider.php on line 138 and defined in /var/www/********/includes/classes/DeviantArt.php:357
Stack trace:
#0 /var/www/********/includes/classes/ImageProvider.php(138): App\DeviantArt::isImageAvailable(NULL)
#1 /var/www/********/includes/classes/ImageProvider.php(21): App\ImageProvider->setUrls('*******')
#2 /var/www/********/includes/classes/Posts.php(207): App\ImageProvider->__construct('******************', Array)
#3 /var/www/********/includes/classes/Controllers/PostController.php(334): App\Posts::checkRequestFinishingImage('***************...')
#4 /var/www/********/includes/classes/RouteHelper.php(11): App\Controllers\PostController->action(Array)
#5 /var/www/********/includes/do.php(27): App\RouteHelper::App\{closure}(Array)
#6 /var/www/********/www/index.php(1): require('/var/www/******...')
#7 {main}
t" while reading response header from upstream, client: **.***.***.***, server: ***********, request: "POST /*************************** HTTP/1.1", upstream: "fastcgi://unix:/run/php/php7.1-fpm.sock:", host: "***********"
此处，stderr 输出在 之后被截断t，这留下了足够的信息来查找问题，但这仍然不是完整的消息。我无法在输出的长度和截断时间之间找到任何模式。
我在 Debian Stretch 上使用 nginx 版本 1.10.3 和 PHP 版本 7.1.8。我还尝试设置以下值nginx.conf（因为我过去曾查找过此问题的解决方案），但上述示例是在这些设置已经生效的情况下生成的。
fastcgi_buffers 256 4k;
client_max_body_size 20M;