Description:
------------
On PHP v5.4.x mysqli_connect() and mysqli_query() worked momentally via named pipes for all version of windows (at least for MySQL v5.5, v5.6, v5.7), but in PHP v5.6.x, v7.0.x, v7.1.x, v7.2.x works very slowly:
~ 50 msec for mysqli_connect()
~ 16 msec for mysqli_query()

Tested on:
PHP: v5.6.36-x64, v7.0.30-x64, v7.1.18-x64, v7.2.6-x64
MySQL: v5.6.24 x64, v5.7.22 x64
OS: Windows Server 2008 R2, Windows Server 2016

32-bit versions of PHP have not yet been tested

=== Output of Test script ===
PHP version      : 7.2.6
MySQL version    : 5.7.22
MySQL server     : \\.\pipe\MySQL via named pipe
Latency (connect): 46.875 ms
Latency (close)  : 0 ms
Latency (query)  : 16.15625 ms
Speed (select)   : 64 req/sec
Speed (insert)   : 63 req/sec
Speed (update)   : 62 req/sec

PHP version      : 7.2.6
MySQL version    : 5.7.22
MySQL server     : localhost via TCP/IP
Latency (connect): 3.90625 ms
Latency (close)  : 0 ms
Latency (query)  : 0.03125 ms
Speed (select)   : 21333 req/sec
Speed (insert)   : 12800 req/sec
Speed (update)   : 10667 req/sec

I think this is a bug, because in the previous version of PHP everything worked is perfect!

Test script:
---------------
$cli = PHP_SAPI == 'cli';
$ln = chr(13).chr(10);
if (!$cli) echo '<pre>';
echo bench_db_format(bench_db('.', 'root', 'pass', 'db_name'), $ln).$ln;
echo bench_db_format(bench_db('localhost', 'root', 'pass', 'db_name'), $ln).$ln;
if (!$cli) echo '<pre>';

more code can be obtained from this link:
http://opti.su/public/bench_db.txt