如何通过Gzip压缩优化PHP网站的访问速度？

通过Gzip压缩可以减小传输的数据量，从而提高PHP网站的访问速度。以下是优化PHP网站访问速度的步骤：

1. 检查服务器是否支持Gzip压缩：在PHP代码中添加以下代码，检查服务器是否支持Gzip压缩：

<?php
if (substr_count($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip')) {
    ob_start("ob_gzhandler");
} else {
    ob_start();
}
?>

2. 启用Gzip压缩：在网站的.htaccess文件中添加以下代码启用Gzip压缩：

<IfModule mod_deflate.c>
    # Compress HTML, CSS, JavaScript, Text, XML and fonts
    AddOutputFilterByType DEFLATE application/javascript
    AddOutputFilterByType DEFLATE application/rss+xml
    AddOutputFilterByType DEFLATE application/vnd.ms-fontobject
    AddOutputFilterByType DEFLATE application/x-font
    AddOutputFilterByType DEFLATE application/x-font-opentype
    AddOutputFilterByType DEFLATE application/x-font-otf
    AddOutputFilterByType DEFLATE application/x-font-truetype
    AddOutputFilterByType DEFLATE application/x-font-ttf
    AddOutputFilterByType DEFLATE application/x-javascript
    AddOutputFilterByType DEFLATE application/xhtml+xml
    AddOutputFilterByType DEFLATE application/xml
    AddOutputFilterByType DEFLATE font/opentype
    AddOutputFilterByType DEFLATE font/otf
    AddOutputFilterByType DEFLATE font/ttf
    AddOutputFilterByType DEFLATE image/svg+xml
    AddOutputFilterByType DEFLATE image/x-icon
    AddOutputFilterByType DEFLATE text/css
    AddOutputFilterByType DEFLATE text/html
    AddOutputFilterByType DEFLATE text/javascript
    AddOutputFilterByType DEFLATE text/plain
    AddOutputFilterByType DEFLATE text/xml

    # Remove browser bugs (only needed for really old browsers)
    BrowserMatch ^Mozilla/4 gzip-only-text/html
    BrowserMatch ^Mozilla/4\.0[678] no-gzip
    BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
    Header append Vary User-Agent
</IfModule>

3. 测试Gzip压缩是否生效：使用工具如GTMetrix或PageSpeed Insights测试网站的访问速度，确保Gzip压缩已经生效。

通过以上步骤，可以通过Gzip压缩优化PHP网站的访问速度，减小传输的数据量，提高网站的加载速度。