RedHat9 kernel2.4.20-46.9.legacysmp i686

最高値
Server Software: Apache/2.0.59
Server Hostname: localhost
Server Port: 80

Document Path: /index.html.en
Document Length: 1456 bytes

Concurrency Level: 10
Time taken for tests: 0.704794 seconds
Complete requests: 10000
Failed requests: 0
Write errors: 0
Total transferred: 17270000 bytes
HTML transferred: 14560000 bytes
Requests per second: 14188.54 [#/sec] (mean)
Time per request: 0.705 [ms] (mean)
Time per request: 0.070 [ms] (mean, across all concurrent requests)
Transfer rate: 23928.98 [Kbytes/sec] received

複数回計測結果
Requests per second: 14188.54 [#/sec] (mean)
Requests per second: 11987.78 [#/sec] (mean)
Requests per second: 11600.58 [#/sec] (mean)
Requests per second: 11532.35 [#/sec] (mean)
Requests per second: 12572.15 [#/sec] (mean)
Requests per second: 11310.46 [#/sec] (mean)
Requests per second: 11814.84 [#/sec] (mean)

CentOS、yumでkernel最新、apacheはソースからインストール。
CentOS i686とx86_64ではあまり変わりがないが
ややx86_64の方がパフォーマンス出ていない感じ。
RedHatもOSクリーンインストール後apt-getでkernel最新、
ソースからapacheを入れて再計測してみたが
CentOSに比べてぶっちぎりでいい数値を出した。
しかしなぜこんなに違うんだろうか。