opcache preload cuts the deploy bill by up to fourteen times — but five of seven frameworks do not hand it to you

The footprint measurement left a number behind: on the first request a fresh container serves, Phalcon takes 2.2 ms and Laravel 72.2 ms — thirty-three times. That is the compile bill the first visitor after a deploy pays. The same record’s environment carried one more line: preload: none.

This record closes that line. One variable.

The gain

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Loads ~60 kB of JavaScript for tooltips and cursor readings. The data table below is always open.

Data table

bench/preload.sh, median of three repeats

Series	Laravel	Symfony	Laminas	CodeIgniter	Yii2	Slim	Phalcon
no preload	76.31 ms	35.58 ms	26.7 ms	20.75 ms	16.98 ms	7.46 ms	2.68 ms
preload on	13.98 ms	2.5 ms	3.81 ms	3.13 ms	4.8 ms	1.86 ms	1.99 ms

The chart is drawn in the browser; the table below carries the same data.

Candidate	no preload	official	classmap	Best gain	fpm cost
Laravel	76.31 ms	none	13.98 ms	5.5×	+2,340 ms
Symfony the largest gain	35.58 ms	2.50 ms	broke	14.2×	−40 ms
Laminas	26.70 ms	none	3.81 ms	7.0×	−7 ms
CodeIgniter	20.75 ms	3.13 ms	5.29 ms	6.6×	−12 ms
Yii2	16.98 ms	none	4.80 ms	3.5×	+13 ms
Slim	7.46 ms	none	1.86 ms	4.0×	+28 ms
Phalcon classes live in the C extension	2.68 ms	none	1.99 ms	1.3×	+43 ms

The footprint record’s thirty-three-fold gap closes under preload: Symfony lands at 2.50 ms, Phalcon’s bare figure. The difference was never the framework’s weight; it was opcache being cold.

But five of them do not have one

Candidate	Official preload	Where
Symfony	yes	var/cache/prod/*.preload.php, produced by warm-up
CodeIgniter	yes	preload.php, in the starter template
Laravel	no	—
Yii2	no	—
Laminas	no	—
Slim	no	—
Phalcon	no	not needed

The second column says more than the first. The gain exists, but in five of the seven it is waiting for the user to write it — and the candidate with the most to gain, Laravel at 76.31 ms, is one of those five.

”Compile everything” is not the answer

For a framework without an official file the obvious fix is to walk Composer’s classmap and compile the lot. The measurement refutes that in two different ways.

On Symfony the container never comes up. Compiling 4,721 files at load time runs into classes that resolve environment variables:

NOTICE: PHP message: [critical] Uncaught Exception:
Environment variable not found: "DEFAULT_URI".

Preload runs in php-fpm’s master process; something dying there means the service never starts at all. The harness records it as ready: false.

On CodeIgniter it is worse than the official file. 3.13 ms official against 5.29 ms for the classmap. Forty-odd hand-picked classes beat 479 compiled blindly: preload fills shared memory, and classes nobody needs take up room.

The cost moves, it does not disappear

Preload takes the compile work out of the request and puts it into php-fpm’s start-up. On small preloads that cost is unmeasurable; on the large one it is unmistakable:

Candidate	Files compiled	Time to first answer	Difference
Laravel paid on every deploy	4,721	2,755 ms	+2,340 ms
Laminas	1,195	352 ms	−7 ms
Yii2	992	352 ms	+13 ms
CodeIgniter	479	324 ms	−12 ms
Slim	138	359 ms	+28 ms
Phalcon	3	362 ms	+43 ms

Laravel’s classmap preload takes 62 ms from every visitor and writes 2.3 seconds into the deploy. On a service with steady traffic that is a good trade — the first visitor pays once and nobody after them pays at all. On a service that deploys ten times a day it inverts: twenty-three seconds of start-up delay against 62 ms for a few hundred visitors.

Phalcon turned into the control group

Only 3 files were compiled out of Phalcon’s classmap — its classes are in a C extension, not in PHP. Its gain is also the smallest at 1.3×. That is the check on what the measurement measures: if preload removes PHP source compilation, it should do nothing for a candidate with no PHP source to compile. It did nothing.

Back to the footprint record

That record said disk size predicts nothing and that the one thing which really separates the candidates is the first request paid while opcache is cold. This measurement adds a condition to that sentence: opcache does not have to stay cold — but whether it does depends on whether your framework handed you a preload file.