性能优化指南

服务器性能优化技巧

本指南将帮助您优化VPS性能，提升网站响应速度和用户体验。

系统级优化

内核参数优化

# 编辑系统参数
vim /etc/sysctl.conf

# 网络优化
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 65536 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
net.ipv4.tcp_congestion_control = bbr

# 文件系统优化
fs.file-max = 65536
vm.swappiness = 10
vm.dirty_ratio = 15
vm.dirty_background_ratio = 5

# 应用配置
sysctl -p

文件描述符限制

# 编辑limits配置
vim /etc/security/limits.conf

# 添加以下内容
* soft nofile 65536
* hard nofile 65536
root soft nofile 65536
root hard nofile 65536

# 重启后生效
ulimit -n 65536

磁盘I/O优化

# 查看当前I/O调度器
cat /sys/block/sda/queue/scheduler

# 设置为deadline调度器（适合SSD）
echo deadline > /sys/block/sda/queue/scheduler

# 永久设置
echo 'echo deadline > /sys/block/sda/queue/scheduler' >> /etc/rc.local

Web服务器优化

Apache性能优化

# /etc/apache2/conf-available/performance.conf

# 启用必要模块
LoadModule rewrite_module modules/mod_rewrite.so
LoadModule deflate_module modules/mod_deflate.so
LoadModule expires_module modules/mod_expires.so
LoadModule headers_module modules/mod_headers.so

# 工作模式优化
<IfModule mpm_prefork_module>
    StartServers 8
    MinSpareServers 5
    MaxSpareServers 20
    ServerLimit 256
    MaxRequestWorkers 256
    MaxConnectionsPerChild 10000
</IfModule>

# 启用压缩
<IfModule mod_deflate.c>
    AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css text/javascript application/javascript application/json
    DeflateCompressionLevel 6
</IfModule>

# 缓存设置
<IfModule mod_expires.c>
    ExpiresActive On
    ExpiresByType image/jpg "access plus 1 year"
    ExpiresByType image/jpeg "access plus 1 year"
    ExpiresByType image/gif "access plus 1 year"
    ExpiresByType image/png "access plus 1 year"
    ExpiresByType text/css "access plus 1 month"
    ExpiresByType application/pdf "access plus 1 month"
    ExpiresByType text/javascript "access plus 1 month"
    ExpiresByType application/javascript "access plus 1 month"
</IfModule>

Nginx性能优化

# /etc/nginx/nginx.conf

# 工作进程数（通常等于CPU核心数）
worker_processes auto;

# 每个工作进程的连接数
events {
    worker_connections 1024;
    use epoll;
    multi_accept on;
}

http {
    # 基本优化
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;
    
    # 缓冲区优化
    client_body_buffer_size 128k;
    client_max_body_size 10m;
    client_header_buffer_size 1k;
    large_client_header_buffers 4 4k;
    output_buffers 1 32k;
    postpone_output 1460;
    
    # Gzip压缩
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_types
        text/plain
        text/css
        text/xml
        text/javascript
        application/json
        application/javascript
        application/xml+rss
        application/atom+xml
        image/svg+xml;
    
    # 缓存设置
    location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
        add_header Vary Accept-Encoding;
    }
}

数据库优化

MySQL性能优化

# /etc/mysql/mysql.conf.d/mysqld.cnf

[mysqld]
# 基本设置
skip-name-resolve
skip-external-locking

# 内存优化
innodb_buffer_pool_size = 512M  # 设置为可用内存的70%
innodb_log_buffer_size = 16M
key_buffer_size = 256M
sort_buffer_size = 2M
read_buffer_size = 2M
read_rnd_buffer_size = 8M
myisam_sort_buffer_size = 64M

# 连接优化
max_connections = 100
thread_cache_size = 16
table_open_cache = 2000
table_definition_cache = 1400

# InnoDB优化
innodb_flush_log_at_trx_commit = 2
innodb_log_file_size = 256M
innodb_flush_method = O_DIRECT
innodb_file_per_table = 1

# 查询缓存
query_cache_type = 1
query_cache_size = 64M
query_cache_limit = 2M

# 慢查询日志
slow_query_log = 1
slow_query_log_file = /var/log/mysql/slow.log
long_query_time = 2

PostgreSQL优化

# /etc/postgresql/14/main/postgresql.conf

# 内存设置
shared_buffers = 256MB
effective_cache_size = 1GB
work_mem = 4MB
maintenance_work_mem = 64MB

# 检查点设置
checkpoint_completion_target = 0.9
wal_buffers = 16MB
default_statistics_target = 100

# 连接设置
max_connections = 100

PHP优化

PHP-FPM配置

# /etc/php/8.1/fpm/pool.d/www.conf

[www]
user = www-data
group = www-data

# 进程管理
pm = dynamic
pm.max_children = 50
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 35
pm.max_requests = 500

# 性能优化
request_terminate_timeout = 300
request_slowlog_timeout = 5s
slowlog = /var/log/php-fpm-slow.log

PHP配置优化

# /etc/php/8.1/fpm/php.ini

# 内存限制
memory_limit = 256M
max_execution_time = 300
max_input_time = 300

# 文件上传
upload_max_filesize = 64M
post_max_size = 64M
max_file_uploads = 20

# OPcache优化
opcache.enable = 1
opcache.memory_consumption = 128
opcache.interned_strings_buffer = 8
opcache.max_accelerated_files = 4000
opcache.revalidate_freq = 60
opcache.fast_shutdown = 1

缓存优化

Redis缓存

# 安装Redis
apt install redis-server

# 配置Redis
vim /etc/redis/redis.conf

# 内存优化
maxmemory 256mb
maxmemory-policy allkeys-lru

# 持久化设置
save 900 1
save 300 10
save 60 10000

Memcached缓存

# 安装Memcached
apt install memcached

# 配置Memcached
vim /etc/memcached.conf

# 内存设置
-m 128
-c 1024
-t 4

网络优化

TCP优化

# /etc/sysctl.conf

# TCP窗口缩放
net.ipv4.tcp_window_scaling = 1

# TCP时间戳
net.ipv4.tcp_timestamps = 1

# TCP SACK
net.ipv4.tcp_sack = 1

# TCP快速回收
net.ipv4.tcp_tw_reuse = 1

# TCP拥塞控制
net.ipv4.tcp_congestion_control = bbr

防火墙优化

# 优化iptables规则
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -m limit --limit 25/minute --limit-burst 100 -j ACCEPT

监控和分析

性能监控脚本

#!/bin/bash
# performance_monitor.sh

echo "=== System Performance Report ===" > /tmp/perf_report.txt
echo "Date: $(date)" >> /tmp/perf_report.txt
echo "" >> /tmp/perf_report.txt

# CPU使用率
echo "CPU Usage:" >> /tmp/perf_report.txt
top -bn1 | grep "Cpu(s)" >> /tmp/perf_report.txt
echo "" >> /tmp/perf_report.txt

# 内存使用
echo "Memory Usage:" >> /tmp/perf_report.txt
free -h >> /tmp/perf_report.txt
echo "" >> /tmp/perf_report.txt

# 磁盘使用
echo "Disk Usage:" >> /tmp/perf_report.txt
df -h >> /tmp/perf_report.txt
echo "" >> /tmp/perf_report.txt

# 网络连接
echo "Network Connections:" >> /tmp/perf_report.txt
netstat -tuln | wc -l >> /tmp/perf_report.txt

网站性能测试

# 使用ab进行压力测试
ab -n 1000 -c 10 http://your-website.com/

# 使用curl测试响应时间
curl -o /dev/null -s -w "Total time: %{time_total}s\n" http://your-website.com/

优化建议

定期维护

清理日志文件：定期清理过大的日志
更新系统：保持系统和软件最新
监控资源：定期检查CPU、内存、磁盘使用情况
优化数据库：定期优化数据库表和索引

硬件升级建议

CPU：多核心处理器提升并发处理能力
内存：增加RAM改善缓存效果
存储：使用SSD提升I/O性能
网络：升级带宽提升访问速度

应用层优化

代码优化：优化算法和数据库查询
图片优化：压缩图片，使用WebP格式
CDN加速：使用内容分发网络
静态资源：启用浏览器缓存