關於proxy有無作用的問題 - BBS

請問一下各位大大.
小弟最近在調整我的 PROXY server
但是有個問題 小第一直無法理解.
照理說.我設定 PROXY 連線.
第一次 因為 PROXY內沒有資料 他到外部去抓
再來應該就是直接回給使用者 之前抓的資料了
但是 我測試了2個網站 發現 以下2個情形.

1.http://taiwan.nba.com --看來似乎有使用到 cache

FreeBSD -root-:http_ping -c 10 -i 2 -proxy proxy:8080 http://taiwan.nba.com
61720 bytes from http://taiwan.nba.com: 446.678 ms (0.366c/439.419r/6.893d)
61720 bytes from http://taiwan.nba.com: 21.316 ms (0.398c/13.801r/7.117d)
61720 bytes from http://taiwan.nba.com: 12.151 ms (0.401c/5.063r/6.687d)
61720 bytes from http://taiwan.nba.com: 20.897 ms (0.443c/13.748r/6.706d)
61720 bytes from http://taiwan.nba.com: 26.035 ms (0.315c/15.723r/9.997d)
61720 bytes from http://taiwan.nba.com: 45.725 ms (0.352c/10.849r/34.524d)
61720 bytes from http://taiwan.nba.com: 23.175 ms (0.34c/3.994r/18.841d)
61720 bytes from http://taiwan.nba.com: 23.202 ms (0.368c/13.35r/9.484d)
61720 bytes from http://taiwan.nba.com: 18.466 ms (0.361c/11.34r/6.765d)
61720 bytes from http://taiwan.nba.com: 52.222 ms (0.382c/12.569r/39.271d)

--- http://taiwan.nba.com http_ping statistics ---
10 fetches started, 10 completed (100%), 0 failures (0%), 0 timeouts (0%)
total min/avg/max = 12.151/68.9867/446.678 ms
connect min/avg/max = 0.315/0.3726/0.443 ms
response min/avg/max = 3.994/53.9856/439.419 ms
data min/avg/max = 6.687/14.6285/39.271 ms

2.http://www.berkeley.edu --看來似乎沒有使用到 cache

FreeBSD -root-:http_ping -c 10 -i 2 -proxy proxy:8080 http://www.berkeley.edu
21695 bytes from http://www.berkeley.edu: 625.539 ms (0.319c/314.987r/310.233d)
21695 bytes from http://www.berkeley.edu: 649.734 ms (0.341c/326.974r/322.419d)
21695 bytes from http://www.berkeley.edu: 650.345 ms (0.28c/327.712r/322.353d)
21695 bytes from http://www.berkeley.edu: 626.176 ms (0.341c/315.58r/310.255d)
21695 bytes from http://www.berkeley.edu: 627.871 ms (0.419c/316.5r/310.952d)
21695 bytes from http://www.berkeley.edu: 650.299 ms (0.358c/327.224r/322.717d)
21695 bytes from http://www.berkeley.edu: 626.325 ms (0.443c/315.453r/310.429d)
21695 bytes from http://www.berkeley.edu: 651.04 ms (0.387c/328.232r/322.421d)
21695 bytes from http://www.berkeley.edu: 650.467 ms (0.464c/327.452r/322.551d)
21695 bytes from http://www.berkeley.edu: 650.768 ms (0.476c/327.597r/322.695d)

--- http://www.berkeley.edu http_ping statistics ---
10 fetches started, 10 completed (100%), 0 failures (0%), 0 timeouts (0%)
total min/avg/max = 625.539/640.856/651.04 ms
connect min/avg/max = 0.28/0.3828/0.476 ms
response min/avg/max = 314.987/322.771/328.232 ms
data min/avg/max = 310.233/317.703/322.717 ms

以上2個狀況.
是先後測試的.
我也確定 cache 的硬碟空間 是有空間的.
但是 為什麼 到很多地方去的時候 他並不會使用 cache 呢?
照理說 第一次到 外面去抓 後面那幾次 不是應該 直接把cache的資料回給使用者嗎??

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