SPEED UP your code

FOR THE PLANET

Carsten Windler

Grafix NewRelic

only bits and bytes?

55,7

Billion electronic devices by 2025

Million tonnes of electronic waste in 2021

~4%

IT's share of total greenhouse gas emissions

~2%

Share of data centres in global
energy consumption

Green Software Engineering

Green Coding

SUSTAINABLE IT

GREEN IT

GREEN SOFTWARE ENGINEERING

SHIFT

RETHINK

REDUCE

PERFORMANCE IN MIND

My Goodness

Why Didn't I Think of That?

How to not do CSV imports:

Load the whole CSV file into memory
Create a Model from every row
Iterate over the Collection of Models
Do some super slow calculations
Use the Model to save the data
...?
Timeout

Let's optimize some code!

class StringPositionBench
{
    public function benchStrContains()
    {
        str_contains('string contains PHP', 'PHP');
    }

    public function benchPregMatch()
    {
        preg_match("/php/i", 'string contains PHP');
    }
}

https://github.com/phpbench/phpbench

AI SUPPORT

$resultArray = [];

for ($i = 0; $i <= 10000; $i++) {
    $resultArray[] = sprintf('%s %d', trans('row'), $i);
}

// Time (seconds): 0.45
// Memory Peak (MB): 80.65

REDUCE FUNCTION CALLS

$resultArray = [];
$transRow = trans('row');

for ($i = 0; $i <= 10000; $i++) {
    $resultArray[] = sprintf('%s %d', $transRow, $i);
}

// Time (seconds): 0.015 (=> 0.03x)
// Memory Peak (MB): 80.65 (=> 1.00x)

STRING CONCATENATION

$transRow = trans('row');
$resultArray = [];

for ($i = 0; $i <= 10000; $i++) {
    $resultArray[] = $transRow . ' ' . $i;
}


// Time (seconds): 0.007 (=> 0.48x)
// Memory Peak (MB): 52.64 (=> 0.65x)

Preallocate array

$transRow = trans('row');
$resultArray = new SplFixedArray(10001);

for ($i = 0; $i <= 10000; $i++) {
    $resultArray[] = $transRow . ' ' . $i;
}

// Time (seconds): 0.0064 (=> 0.94x)
// Memory Peak (MB): 52.14 (=> 0.99x)

OVERALL

$transRow = trans('row');
$resultArray = new SplFixedArray(10001);

for ($i = 0; $i <= 10000; $i++) {
    $resultArray[] = $transRow . ' ' . $i;
}

// From:
// Time (seconds): 0.45
// Memory Peak (MB): 80.65

// To:
// Time (seconds): 0.0064 (=> 0.01x)
// Memory Peak (MB): 52.15 (=> 0.65x)

🎉

PROFILING

What else?

LIFECYCLE OF An HTTP REQUESt

Bootstrap

Business Logic

Finish

.env

config

routes

middlewarez!!!1

events

DI container

observers

service providers

validators

Bootstrap

Business Logic

Finish

PACKAGES

*Runs/second

Guzzle

14.553*

Nyholm

17.734*

=> approx. 21% faster!

class DateFormatBench
{
    public function benchDate()
    {
        date('D M d Y H:m:s');
    }

    public function benchDateTime()
    {
        (new \DateTime())->format('D M d Y H:m:s');
    }

    public function benchCarbon()
    {
        (new Carbon\Carbon())->format('D M d Y H:m:s');
    }
}

Carbon has 180+ language files

approx. 3,5 MB

PACKAGE Footprint

https://carstenwindler.de/green-it/why-phps-carbon-is-bad-for-the-climate/

Carbon has 200,000 daily installs
3 MB language files downloaded in vain
200,000 x 3 MB x 365 = 213,687 GB
0.81 kWh/GB of data traffic*
442 gCO2e/kWh*
213,687 GB × 0.81 kWh/GB = 173,086 kWh
173,086 kWh × 442 gCO2e/kWh = 76,504,219 gCO2e

70+ tCO2e per year

wasted

CARBONS CARBON

* https://sustainablewebdesign.org/calculating-digital-emissions/

fzaninotto/Faker

* https://marmelab.com/blog/2020/10/21/sunsetting-faker.html
https://www.pexels.com/photo/red-sunset-over-water-10276693/

🪦

Over the years, Faker has probably emitted more than 11 Metric tons of CO2 equivalent. Being such a significant contributor to climate change kills me.

François Zaninotto*

composer require everything

ARCHITECTURE

https://unsplash.com/photos/FO2zwDMQzUM

DATABASE

Use the right tool for the job
- SQL
- NoSQL
- Key/Value
Learn about performance tweaks
- Indexes
- Projection
- Slow query log
- EXPLAIN statement
- ORM necessary?

https://unsplash.com/photos/Wpnoqo2plFA

Table performance_tests
500,000 rows
half of them have some_flag = 1
export id, first_name, last_name

EXAMPLE: CSV EXPORT

$stmt = DB::select(
    'SELECT * FROM performance_tests WHERE some_flag = 1'
);

$fp = fopen('/tmp/export.csv', 'wb');

foreach ($stmt as $row) {
    $fields = [
        $row->id,
        $row->first_name,
        $row->last_name,
    ];

    fputcsv($fp, $fields);
}

fclose($fp);

// #1: Raw SQL
DB::select(
   'SELECT * 
   FROM performance_tests WHERE some_flag = 1'
);

// Time: 1.02s
// Memory Peak: 242.71 MB

// #2: Raw SQL + projection
DB::select(
   'SELECT id, first_name, last_name 
   FROM performance_tests WHERE some_flag = 1'
);

// Time: 0.74s
// Memory Peak: 191.62 MB

// #3: Raw SQL + cursor
DB::cursor(
   'SELECT * 
   FROM performance_tests WHERE some_flag = 1'
);

// Time: 0.78s
// Memory Peak: 82.2 MB

// #4: Raw SQL + cursor + projection
DB::cursor(
   'SELECT id, first_name, last_name 
   FROM performance_tests WHERE some_flag = 1'
);

// Time: 0.70s
// Memory Peak: 63.17 MB

Type	Time (s)	Memory Peak (MB)
Raw SQL	1.02	243
Raw SQL + projection	0.73	192
Raw SQL + cursor	0.78	82
Raw SQL + projections + cursor	0.70	63

$result = PerformanceTest::where('some_flag', '=', 1)->get();

$fp = fopen('/tmp/export.csv', 'wb');

foreach ($result as $performanceTest) {
    $fields = [
        $performanceTest->id,
        $performanceTest->first_name,
        $performanceTest->last_name,
    ];

    fputcsv($fp, $fields);
}

fclose($fp);

// #5: Eloquent
PerformanceTest::where('some_flag', '=', 1)->get();

// Time: 3.74s
// Memory Peak: 378.92 MB

// #6: Eloquent + projection
$result = PerformanceTest::where('some_flag', '=', 1)
    ->select(['id', 'first_name', 'last_name'])
    ->get();

// Time: 3.48s
// Memory Peak: 345.10 MB

// #7: Eloquent + lazy
PerformanceTest::where('some_flag', '=', 1)->lazy();

// Time: 21.63s
// Memory Peak: 55.1 MB

// #8: Eloquent + cursor
PerformanceTest::where('some_flag', '=', 1)->cursor();

// Time: 4.14s
// Memory Peak: 85.47 MB

// #9: Eloquent + Collection filter
PerformanceTest::get()->where('some_flag', '=', 1);

// Time: 7.77s
// Memory Peak: 705.52 MB

PerformanceTest::where('some_flag', '=', 1)->get();

Type	Time (s)	Memory Peak (MB)
Eloquent	3.74	379
Eloquent + projection	3.48	345
Eloquent + lazy	21.63	55
Eloquent + cursor	4.14	85
Eloquent + cursor + projection	3.99	66
Eloquent + collection filter	7.77	705

Type	Time (s)	Memory Peak (MB)
Raw SQL	1.02	243
Raw SQL + projection	0.73	192
Raw SQL + cursor	0.78	82
Raw SQL + projections + cursor	0.70	63

Type	Time (s)	Memory Peak (MB)
Eloquent	3.74	379
Eloquent + projection	3.48	345
Eloquent + lazy	21.63	55
Eloquent + cursor	4.14	85
Eloquent + cursor + projection	3.99	66
Eloquent + collection filter	7.77	705

There is so much more...

Hosting
Cloud services
Time
- Developer
- CI/CD
- QA
- Product manager
- SEO
- Customer satisfaction

MONEY

THANK YOU

Carsten Windler

Principal Engineer @

https://www.linkedin.com/in/cwindler

https://carstenwindler.de

https://plana.earth

APIs

Source: Cloudflare

Avoid API calls
- Caching
Reduce amount of data
- Is all information necessary?
Split up endpoints
- GET /users/12
- GET /users/12/address
Specify fields
- GET /users/12?fields=id,last_name

APIs

https://www.pexels.com/photo/woman-writing-on-whiteboard-3861943/

Log only what is necessary
Data retention
Garbage collectors / log rotation
Compression / file formats

https://www.pexels.com/photo/black-trash-bin-with-full-of-trash-3806764/

STorage

CACHING

Byte code cache (OPcache)
Proxy cache (CDN)
HTTP cache (Varnish)
Server-side caching (Redis)
Client-side caching (Browser)
In-Memory-Caching

There are only two hard things in Computer Science: cache invalidation and naming things.

— Phil Karlton

OPcache

Check if enabled
- php.ini
- rlerdorf/opcache-status
Optimize memory usage, e.g.
- opcache.memory_consumption=256
- opcache.max_accelerated_files=20000
Disable timestamp validation
- opcache.validate_timestamps=0
- opcache_reset()

IN-MEMORY CACHING

$cache = [];

for ($i = 1; $i <= 10000; $i++) {
    $randomNumber = random_int(1, 100);

    if (isset($cache[$randomNumber])) {
        $result = $cache[$randomNumber];
    } else {
        $result = sqrt($randomNumber);

        $cache[$randomNumber] = $result;
    }

    echo $result;
}

// Vergleich mit CodeBench

SERVERLESS / Faas

Speed up your code

By Carsten Windler

Speed up your code

How to improve PHP code to emit less carbon. Talk on the PHP Developer Day 2023 in Dresden, 22.09.2023.

Carsten Windler

carstenwindler.de

SPEED UP your code

only bits and bytes?

SUSTAINABLE IT

GREEN IT

GREEN SOFTWARE ENGINEERING

PERFORMANCE IN MIND

AI SUPPORT

REDUCE FUNCTION CALLS

STRING CONCATENATION

Preallocate array

OVERALL

PROFILING

LIFECYCLE OF An HTTP REQUESt

PACKAGES

PACKAGE Footprint

CARBONS CARBON

ARCHITECTURE

DATABASE

EXAMPLE: CSV EXPORT

MONEY

APIs

APIs

STorage

CACHING

OPcache

IN-MEMORY CACHING

SERVERLESS / Faas

Speed up your code

More from Carsten Windler