Plack::Middleware::SizeLimit - Terminate processes if they grow too large
use Plack::Builder;
builder {
enable SizeLimit => (
max_unshared_size_in_kb => '4096', # 4MB
# min_shared_size_in_kb => '8192', # 8MB
# max_process_size_in_kb => '16384', # 16MB
check_every_n_requests => 2,
log_when_limits_exceeded => 1
);
$app;
};
This middleware is a port of the excellent Apache::SizeLimit module
for multi-process Plack servers, such as Starman, Starlet,
Gazelle and uWSGI
.
This middleware only works when the environment psgix.harakiri
is
set to a true value by the Plack server. If it's set to false, then this
middleware simply does nothing.
You must use at least version 0.2006 of Starman (July 2010), and 0.19 of Starlet (June 2013). Earlier versions ignore the flag to stop the process.
-
max_unshared_size_in_kb
The maximum amount of unshared memory the process can use; usually this option is all one needs.
Experience on one heavily trafficked mod_perl site showed that setting this option and leaving the others unset is the most effective policy.
This is because it only kills off processes that are truly using too much physical RAM, allowing most processes to live longer and reducing the process churn rate.
-
min_shared_size_in_kb
Sets the minimum amount of shared memory the process must have.
-
max_process_size_in_kb
The maximum size of the process, including both shared and unshared memory.
-
check_every_n_requests
Since checking the process size can take a few system calls on some platforms (e.g. linux), you may specify this option to check the process size every N requests. The default value for N is 1, i.e. to check after the processing of every request.
-
log_when_limits_exceeded
When true, the middleware will log a warning whenever it signals to the server that the process is to be terminated. This is false by default.
Audrey Tang cpan@audreyt.org
This work is under the CC0 1.0 Universal license.
To the extent possible under law, 唐鳳 has waived all copyright and related or neighboring rights to Plack::Middleware::SizeLimit.
This work is published from Taiwan.