Huge memory usage, despite using SapiStreamEmitter about laminas-diactoros HOT 3 CLOSED

First, for anyone reading this, you need to apply PR #233 before running this code.

@sasezaki your suggestion will not work. However, may be interesting to add an "ob_end_flush" at the end of "listen" method (not ob_end_clean).

In order to reduce memory usage is necessary a call to "ob_flush" after each "read" call in SapiStreamEmitter.php.

However I believe this may cause performance issues in most production environments.

The flush calls has a very high performance cost.

And besides this, the PHP engine already regularly flushes output buffer, following "output_buffering" configuration directive.

Which I believe is more appropriate because it allows the application admin to choose the best balance between resource consumption and performance.

And depending of layers beyond PHP engine, the "ob_flush" may be pointless (e.g. Apache buffering when using gzip).

Originally posted by @fcabralpacheco at zendframework/zend-diactoros#232 (comment)

from laminas-diactoros.

It has been months (literally) since I started looking for a solution.

In my case, here is what did the trick - Note that I'm only using the SapiStreamEmitter:

ob_end_flush();
ob_implicit_flush();
$emitter->emit($response);

I'm not sure if this is really efficient, but at least it works (with large files ofc). I still need to try it in prod though..

Not taking any credit here. In fact, this is from an answer (that have some up votes) on ob_implicit_flush() function at php.net: https://secure.php.net/manual/fr/function.ob-implicit-flush.php#116748

EDIT - After some more investigation.. We can simply do this. Way more cleaner.

ob_implicit_flush();
$maxBufferLevel = 0; // Stands for the maximum (and last) output buffering level to unwrap
$emitter->emit($response, $maxBufferLevel);

Originally posted by @cocochepeau at zendframework/zend-diactoros#232 (comment)

from laminas-diactoros.

SapiEmitter no longer part of laminas-diactoros

from laminas-diactoros.