X
ab -n 5000 -c 20 http://drupal.local/
X
Concurrency Level:      20
Time taken for tests:   8.424 seconds
Complete requests:      5000
Failed requests:        0
Write errors:           0
Total transferred:      75050000 bytes
HTML transferred:       72400000 bytes
Requests per second:    593.55 [#/sec] (mean)
Time per request:       33.696 [ms] (mean)
Time per request:       1.685 [ms] (mean, across all concurrent requests)
Transfer rate:          8700.39 [Kbytes/sec] received

Ohne APC:

X
[..]
Time taken for tests:   23.670 seconds
[..]
Requests per second:    211.24 [#/sec] (mean)
Time per request:       94.678 [ms] (mean)
[..]