如何使用curl来比较启用了deflate的页面大小,而不使用它

Question

我mod_deflate启用了apache .我想找出mod_deflate启用和不启用页面的大小,并比较大小的性能.在curl中,我似乎要求服务器使用--compressed和发送正常的gzip压缩内容,但似乎无法找到该页面的大小.知道怎么做吗？

curl --head http://site

HTTP/1.1 200 OK
Date: Wed, 08 Feb 2012 08:48:04 GMT
Server: Apache/2.2.14 (Unix) mod_ssl/2.2.14 OpenSSL/0.9.7a mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635
X-Powered-By: PHP/5.2.12
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Set-Cookie: PHPSESSID=ce39b051a9cd493cbe4a86056e11d61f; path=/
Vary: Accept-Encoding
Content-Type: text/html

curl --head --compressed http://site

HTTP/1.1 200 OK
Date: Wed, 08 Feb 2012 08:48:19 GMT
Server: Apache/2.2.14 (Unix) mod_ssl/2.2.14 OpenSSL/0.9.7a mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635
X-Powered-By: PHP/5.2.12
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Set-Cookie: PHPSESSID=513b8ac5818fd043471c8aac44355898; path=/
Vary: Accept-Encoding
Content-Encoding: gzip
Content-Length: 20
Content-Type: text/html

Answer 1

我认为获得大小的唯一可靠方法是实际下载文件.但是,curl提供了一个非常方便的选项,仅用于输出感兴趣的数据

-w/--write-out <format>
    Defines what to display on stdout after a completed and successful operation.

[...]

size_download  The total amount of bytes that were downloaded.

这意味着你可以这样做:

curl -so /dev/null http://www.whatsmyip.org/http-compression-test/ -w '%{size_download}'

输出:

8437

并获得压缩大小:

curl --compressed -so /dev/null http://www.whatsmyip.org/http-compression-test/ -w '%{size_download}'

输出:

3225

之后,您的比较应该是微不足道的.

Answer 2

复制/粘贴准备好和人类可读

基于@flesk答案,并在这这里是脚本的人类可读的版本:

#!/usr/bin/env bash
set -e

bytesToHuman() {
    b=${1:-0}; d=''; s=0; S=(Bytes {K,M,G,T,E,P,Y,Z}iB)
    while ((b > 1024)); do
        d="$(printf ".%02d" $((b % 1024 * 100 / 1024)))"
        b=$((b / 1024))
        let s++
    done
    echo "$b$d ${S[$s]}"
}

compare() {
  echo "URI: ${1}"

  SIZE=$(curl -so /dev/null "${1}" -w '%{size_download}')
  SIZE_HUMAN=$(bytesToHuman "$SIZE")
  echo "Uncompressed size : $SIZE_HUMAN"

  SIZE=$(curl --compressed -so /dev/null "${1}" -w '%{size_download}')
  SIZE_HUMAN=$(bytesToHuman "$SIZE")
  echo "Compressed size   : $SIZE_HUMAN"
}

compare https://stackoverflow.com/q/9190190/1480391

输出:

URI: https://stackoverflow.com/q/9190190/1480391
Uncompressed size : 106.69 KiB
Compressed size   : 24.47 KiB