标签: 监控

一、性能调优概述

1.1 性能优化层次

1.2 性能问题诊断流程

-- 1. 检查系统整体状态
SELECT
    numbackends AS connections,
    xact_commit AS commits,
    xact_rollback AS rollbacks,
    blks_read AS disk_reads,
    blks_hit AS cache_hits,
    round(100.0 * blks_hit / NULLIF(blks_read + blks_hit, 0), 2) AS cache_hit_ratio,
    tup_returned AS rows_returned,
    tup_fetched AS rows_fetched,
    tup_inserted AS rows_inserted,
    tup_updated AS rows_updated,
    tup_deleted AS rows_deleted
FROM pg_stat_database
WHERE datname = current_database();

-- 2. 检查活动连接
SELECT
    state,
    COUNT(*) AS count,
    MAX(NOW() - query_start) AS max_duration
FROM pg_stat_activity
GROUP BY state;

-- 3. 检查慢查询
SELECT
    pid,
    NOW() - query_start AS duration,
    query,
    state
FROM pg_stat_activity
WHERE state != 'idle'
AND query_start < NOW() - INTERVAL '5 seconds'
ORDER BY duration DESC;

-- 4. 检查锁等待
SELECT
    blocked.pid AS blocked_pid,
    blocked.query AS blocked_query,
    blocking.pid AS blocking_pid,
    blocking.query AS blocking_query
FROM pg_stat_activity blocked
JOIN pg_locks blocked_locks ON blocked.pid = blocked_locks.pid
JOIN pg_locks blocking_locks ON
    blocked_locks.locktype = blocking_locks.locktype
    AND blocked_locks.relation = blocking_locks.relation
    AND blocked_locks.pid != blocking_locks.pid
JOIN pg_stat_activity blocking ON blocking_locks.pid = blocking.pid
WHERE NOT blocked_locks.granted;

HSXISAWD2026/3/20大约 16 分钟

Redis 性能优化与运维

一、性能基准与瓶颈分析

1.1 Redis 性能基准

Redis 的理论性能：

指标	数值
QPS（简单命令）	10W+/s
QPS（复杂命令）	1W+/s
读写延迟	微秒级（<1ms）
网络带宽	可达 1GB/s

HSXISAWD2026/3/20大约 11 分钟

日志管理与监控

日志配置详解

access_log 配置

http {
    # 基本语法
    # access_log path [format [buffer=size] [gzip[=level]] [flush=time] [if=condition]];

    # 定义日志格式
    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';

    # 使用日志格式
    access_log /var/log/nginx/access.log main;

    # 带缓冲的日志（提高性能）
    access_log /var/log/nginx/access.log main buffer=32k flush=5s;

    # 压缩日志
    access_log /var/log/nginx/access.log.gz main gzip=9 buffer=32k;

    server {
        # 站点专用日志
        access_log /var/log/nginx/example.access.log main;

        # 关闭特定路径的日志
        location /health {
            access_log off;
            return 200 "OK";
        }

        # 静态资源不记录日志
        location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
            access_log off;
        }
    }
}

HSXISAWD2026/3/20大约 8 分钟