How to disable output buffering in nginx for PHP application

Question

We have code similar to this:

<?php
    ob_implicit_flush(true);
    ob_end_flush();

    foreach ($arrayOfStrings as $string) {
        echo time_expensive_function($string);
    }
?>

In Apache, this would send each echo to the browser as it was output. In nginx/FastCGI however, this doesn't work due tot he way nginx works (by default).

Is it possible to make this work on nginx/FastCGI, and if so, how?

mad · Accepted Answer · 2020-02-18T22:00:05.900

32

First php has to correctly flush everything :

@ob_end_flush();
@flush();

Then, I found two working solutions:

1) Via Nginx configuration:

fastcgi_buffering off;

2) Via HTTP header in the php code

header('X-Accel-Buffering: no');

edited Feb 18 '20 at 22:00

answered Jul 29 '14 at 14:04

mad

655
6
10

11

just adding `header('X-Accel-Buffering: no');` worked for me :) – Ifnot Sep 01 '15 at 09:48
1

header('X-Accel-Buffering: no'); worked for me, thank you sir for that, spent 2 hours googling and nothing worked only this – aeroson Nov 10 '15 at 07:26
fastcgi_buffering off; in the nginx.conf worked for me, thanks! – Shean Hoxie Jan 08 '16 at 19:33
2

Thanks! The `header('X-Accel-Buffering: no');` worked for me, too! – Chris Haas Feb 26 '16 at 17:13
`header('X-Accel-Buffering: no');` worked for me. Thanks! – Riz Jul 19 '18 at 23:02
You are the savior!!! Adding @ob_end_flush(); @flush(); solved the issue. Only changing header didn't solve the issue. – Vaibhavraj Roham Oct 18 '19 at 19:25

score 5 · Answer 2 · answered Nov 30 '12 at 09:28

5

Easy solution:

fastcgi_keep_conn on; # < solution

proxy_buffering off;
gzip off;

answered Nov 30 '12 at 09:28

Ondrej Prochazka

710
8
9

Actually like you said, `fastcgi_keep_conn on;` was the secret word. – Mohammad AbuShady Jun 03 '13 at 01:33
why isnt the fastcgi_keep_conn directive documented ? – Silver Moon Jun 24 '13 at 13:20
Thank you so much! You saved my day. – Jekis May 12 '14 at 07:21
1

where do these go? – Typel Jul 18 '18 at 17:57
You can use it in nginx http, server or location . http://nginx.org/en/docs/http/ngx_http_fastcgi_module.html#fastcgi_keep_conn – Ondrej Prochazka Sep 18 '19 at 10:20

score 3 · Answer 3 · answered Jun 27 '13 at 10:13

I didn't want to have to turn off gzip for the whole server or a whole directory, just for a few scripts, in a few specific cases.

All you need is this before anything is echo'ed:

header('Content-Encoding: none;');

Then do the flush as normal:

ob_end_flush();
flush();

Nginx seems to pick up on the encoding having been turned off and doesn't gzip.

score 0 · Answer 4 · answered Aug 28 '12 at 19:20

0

Add the flush() function in your loop:

foreach ($arrayOfStrings as $string) {
  echo time_expensive_function($string);
  flush();
}

It might work, but not necessarily on each iteration (there's some magic involved!)

answered Aug 28 '12 at 19:20

Parallelis

681
3
5

score 0 · Answer 5 · answered Jun 11 '13 at 07:33

Add the -flush to the FastCGI config, refer to the manual:

From http://mailman.fastcgi.com/pipermail/fastcgi-developers/2009-July/000286.html

score 0 · Answer 6 · answered Sep 19 '19 at 11:06

I needed both of those two lines at the beginning of my script:

header('X-Accel-Buffering: no');
ob_implicit_flush(true);

Each line alone would also work, combining them makes my browser getting the result from the server even faster. Cannot explain it, just experienced it.

My configuration is nginx with php-fpm.

How to disable output buffering in nginx for PHP application

6 Answers6

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