使用curl进行网络诊断

   我们使用浏览器插件，很容易查看到网页细分请求消耗的时间。如Firefox的Firebug插件：51Testing软件测试网1B7fs9A4K-`

51Testing软件测试网\[1uSC2@[
Linux的命令行怎样实现类似功能呢？curl即可实现：

%X&f"Ub!p7Q!PX0/usr/bin/curl --no-keepalive --no-sessionid --noproxy -o /dev/null -s -w'time_namelookup=%{time_namelookup}
Hp }J,[ {*u0time_connect=%{time_connect}
0d:lDg m0time_appconnect=%{time_appconnect}
V R;WUP F/G0time_pretransfer=%{time_pretransfer}
m&{(T)p+J'z:s(i9}0time_redirect=%{time_redirect}
/f&~)Kk*e9FSth0time_starttransfer=%{time_starttransfer}51Testing软件测试网%Vp*[@MD%h6r
size_download=%{size_download}51Testing软件测试网0O!i0xX'V*\3R
}
size_upload=%{size_upload}
H-e{+f2lvU/~:BA0size_header=%{size_header}
(L,qN~9i7cQ0size_request=%{size_request}51Testing软件测试网]%^L{E7TwH o
speed_download=%{speed_download}51Testing软件测试网 G7Xc7El
speed_upload=%{speed_upload}51Testing软件测试网9GLVt0n {6m2VK'`W#o~
content_type=%{content_type}51Testing软件测试网W}hxU/r4N4J*Ww
num_connects=%{num_connects}
]:u)dkM0num_redirects=%{num_redirects}51Testing软件测试网 {/m~ U)?3R OBfo
redirect_url=%{redirect_url}51Testing软件测试网R"dp+J-E'WQ
time_total=%{time_total}\n'http://www.baidu.com/img/baidu_sylogo1.gif -v --trace-time51Testing软件测试网5c?7N2hPc3Nxi h-Lk

"Q)\,Dg#ux%q0获取结果如下：51Testing软件测试网q9Ik6}+Ix0f%l'p

51Testing软件测试网:r:?2b
yZC

J{(\LI5`"Z |3C004:15:55.518146 * About to connect() to www.baidu.com port 80 (#0)

\J(ZM_LO]J*k004:15:55.518227 * Trying 220.181.112.143... connected

04:15:55.556297 * Connected to www.baidu.com (220.181.112.143) port 80 (#0)51Testing软件测试网~U9k(?F\|"\&Em#T?

3k[Z/@C |c004:15:55.556379 > GET /img/baidu_sylogo1.gif HTTP/1.151Testing软件测试网,h9T(G|(oj{*O"i'D&Zd

(Vvg3Z {}8C?004:15:55.556379 > User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.12.7.0 zlib/1.2.3 libidn/1.18 libssh2/1.2.251Testing软件测试网0M[ _1d4o0^)\

k"Q G$\KdN4|004:15:55.556379 > Host: www.baidu.com51Testing软件测试网!t R2Zu1NF$J+v

9f$WpF2f ^GV)g004:15:55.556379 > Accept: */*51Testing软件测试网N6}pr"gn%r

,wW\X_{c@004:15:55.556379 >51Testing软件测试网~2y`?0R9b%M?6jP

B7WZu
`]X#[ Up004:15:55.597388 < HTTP/1.1 200 OK51Testing软件测试网T Oq~b%B[[$G

D l"s0gP LQ004:15:55.597427 < Date: Fri, 10 Feb 2012 04:59:24 GMT

04:15:55.597459 < Server: Apache51Testing软件测试网i S&S9l;JWpA

j7U dPA:|s004:15:55.597490 < P3P: CP=" OTI DSP COR IVA OUR IND COM "

04:15:55.597521 < Set-Cookie: BAIDUID=HIGKOO6B478BD35F87D2A1F38AC765FE:FG=1; expires=Sat, 09-Feb-13 04:59:24 GMT; max-age=31536000; path=/; domain=.baidu.com; version=151Testing软件测试网%X+jB%G~1\

DPs B \cs/v004:15:55.597553 < Last-Modified: Thu, 20 Jan 2011 07:15:35 GMT

AK3?iL8l,ZL%d004:15:55.597584 < ETag: "66e-49a41e65988c2"51Testing软件测试网'O2}GBhF1P(B:hb

}uEi.AF{004:15:55.597615 < Accept-Ranges: bytes51Testing软件测试网4d"XSA#G

B!@T;Zvjb+Zh4E,[004:15:55.597646 < Content-Length: 163051Testing软件测试网^Wu7DGF

2wU4mV)`a.rx^ @004:15:55.597677 < Cache-Control: max-age=315360000

0w
Nsasle){ q;Q004:15:55.597707 < Expires: Mon, 07 Feb 2022 04:59:24 GMT

04:15:55.597739 < Connection: Keep-Alive

;Y5^v$d7F,t;l3]y004:15:55.597771 < Content-Type: image/gif51Testing软件测试网}F%fji4j?

04:15:55.597802 < data...51Testing软件测试网Gg?u~wI

Yy4W/HJe0time_namelookup=0.011

vqk{)N:g5E1_ H0time_connect=0.049

time_appconnect=0.000

time_pretransfer=0.04951Testing软件测试网5Ov2H0`oQ

.VZ!Re,xY$v-QG0time_redirect=0.00051Testing软件测试网.b&}"Z@7|_zO%d

time_starttransfer=0.090

&}:[7gh+F8e0size_download=1630

size_upload=0

8M6UP|Wk0size_header=50551Testing软件测试网_{N.be

8|:vCf1D1?$`}0size_request=190

D
Th M ]0speed_download=18030.000

speed_upload=0.000

content_type=image/gif

num_connects=151Testing软件测试网 X(h4QiI

num_redirects=051Testing软件测试网1^6}`E.s;a

h8~%R-iL bq!R9O0redirect_url=51Testing软件测试网 K.Oc/B"J3X&{

~/n5K0Ru,t0time_total=0.090

04:15:55.598190 * Closing connection #0