Nginx 整体架构图和时序图

1. 概述

本文档提供Nginx的整体架构图、时序图和模块交互图，帮助开发者从宏观角度理解Nginx的设计架构和运行机制。

2. 整体架构图

2.1 系统层次架构

graph TB
    subgraph "Application Layer"
        A[HTTP Modules]
        B[Mail Modules]
        C[Stream Modules]
    end
    
    subgraph "Core Layer"
        D[Core Modules]
        E[Event Modules]
        F[Configuration System]
    end
    
    subgraph "OS Layer"
        G[OS Abstraction]
        H[Network I/O]
        I[File I/O]
    end
    
    A --> D
    B --> D
    C --> D
    D --> G
    E --> H
    F --> D
    G --> H
    G --> I

2.2 进程架构图

graph TB
    subgraph "Master Process"
        M[Master Process<br/>- Configuration Management<br/>- Worker Management<br/>- Signal Handling]
    end
    
    subgraph "Worker Processes"
        W1[Worker Process 1<br/>- Request Processing<br/>- Event Loop<br/>- Connection Handling]
        W2[Worker Process 2<br/>- Request Processing<br/>- Event Loop<br/>- Connection Handling]
        W3[Worker Process N<br/>- Request Processing<br/>- Event Loop<br/>- Connection Handling]
    end
    
    subgraph "Helper Processes"
        CM[Cache Manager<br/>- Cache Maintenance<br/>- Memory Management]
        CL[Cache Loader<br/>- Cache Loading<br/>- Initialization]
    end
    
    M --> W1
    M --> W2
    M --> W3
    M --> CM
    M --> CL
    
    subgraph "Shared Resources"
        SHM[Shared Memory<br/>- Configuration<br/>- Statistics<br/>- Cache Data]
        SOCK[Socket Descriptors<br/>- Listening Sockets<br/>- Connection Pool]
    end
    
    W1 -.-> SHM
    W2 -.-> SHM
    W3 -.-> SHM
    W1 -.-> SOCK
    W2 -.-> SOCK
    W3 -.-> SOCK

2.3 模块架构图

graph TB
    subgraph "HTTP Modules"
        HC[HTTP Core]
        HR[HTTP Rewrite]
        HA[HTTP Access]
        HG[HTTP Gzip]
        HP[HTTP Proxy]
        HF[HTTP FastCGI]
        HS[HTTP SSL]
    end
    
    subgraph "Event Modules"
        EC[Event Core]
        EE[Epoll Module]
        EK[Kqueue Module]
        ES[Select Module]
    end
    
    subgraph "Core Modules"
        CC[Core Module]
        CR[Regex Module]
        CT[Thread Pool]
    end
    
    subgraph "Mail Modules"
        MC[Mail Core]
        MI[IMAP Module]
        MP[POP3 Module]
        MS[SMTP Module]
    end
    
    subgraph "Stream Modules"
        SC[Stream Core]
        SP[Stream Proxy]
        SL[Stream Limit]
    end
    
    HC --> CC
    HR --> HC
    HA --> HC
    HG --> HC
    HP --> HC
    HF --> HC
    HS --> HC
    
    EC --> CC
    EE --> EC
    EK --> EC
    ES --> EC
    
    MC --> CC
    MI --> MC
    MP --> MC
    MS --> MC
    
    SC --> CC
    SP --> SC
    SL --> SC

3. 启动时序图

3.1 Master进程启动时序

sequenceDiagram
    participant OS as Operating System
    participant M as Master Process
    participant C as Configuration
    participant W as Worker Process
    participant CM as Cache Manager

    OS->>M: Start nginx
    M->>M: ngx_debug_init()
    M->>M: ngx_strerror_init()
    M->>M: ngx_get_options()
    M->>M: ngx_time_init()
    M->>M: ngx_log_init()
    M->>M: ngx_os_init()
    M->>M: ngx_preinit_modules()
    
    M->>C: ngx_init_cycle()
    C->>C: Create memory pool
    C->>C: Parse configuration
    C->>C: Initialize modules
    C-->>M: Return cycle
    
    M->>M: ngx_init_signals()
    M->>M: ngx_daemon()
    M->>M: ngx_create_pidfile()
    
    alt Single Process Mode
        M->>M: ngx_single_process_cycle()
    else Master Process Mode
        M->>M: ngx_master_process_cycle()
        M->>W: ngx_start_worker_processes()
        M->>CM: ngx_start_cache_manager_processes()
        
        loop Master Event Loop
            M->>M: sigsuspend()
            M->>M: Handle signals
            M->>W: Manage workers
        end
    end

3.2 Worker进程启动时序

sequenceDiagram
    participant M as Master Process
    participant W as Worker Process
    participant E as Event System
    participant H as HTTP System

    M->>W: ngx_spawn_process()
    W->>W: ngx_worker_process_cycle()
    W->>W: ngx_worker_process_init()
    
    W->>W: Set process title
    W->>W: Set CPU affinity
    W->>W: Set priority
    W->>W: Set resource limits
    
    W->>W: Initialize modules
    loop Module Initialization
        W->>W: module->init_process()
    end
    
    W->>E: Initialize event system
    E->>E: ngx_event_process_init()
    E->>E: Create connection pool
    E->>E: Initialize event methods
    
    W->>H: Initialize HTTP system
    H->>H: ngx_http_optimize_servers()
    H->>H: Initialize virtual servers
    
    loop Worker Event Loop
        W->>E: ngx_process_events_and_timers()
        E->>E: Process network events
        E->>E: Process timer events
        E->>H: Handle HTTP requests
    end

4. HTTP请求处理时序图

4.1 完整HTTP请求处理流程

sequenceDiagram
    participant C as Client
    participant W as Worker Process
    participant E as Event System
    participant H as HTTP Core
    participant P as Phase Engine
    participant F as Filter Chain
    participant U as Upstream

    C->>W: TCP Connection
    W->>E: Accept connection
    E->>E: ngx_event_accept()
    E->>H: ngx_http_init_connection()
    
    C->>W: HTTP Request
    W->>E: Read event triggered
    E->>H: ngx_http_init_request()
    H->>H: ngx_http_create_request()
    
    H->>H: ngx_http_process_request_line()
    H->>H: Parse request line
    H->>H: ngx_http_process_request_headers()
    H->>H: Parse request headers
    
    H->>H: ngx_http_process_request()
    H->>P: ngx_http_handler()
    P->>P: ngx_http_core_run_phases()
    
    loop Phase Processing
        P->>P: NGX_HTTP_POST_READ_PHASE
        P->>P: NGX_HTTP_SERVER_REWRITE_PHASE
        P->>P: NGX_HTTP_FIND_CONFIG_PHASE
        P->>P: NGX_HTTP_REWRITE_PHASE
        P->>P: NGX_HTTP_POST_REWRITE_PHASE
        P->>P: NGX_HTTP_PREACCESS_PHASE
        P->>P: NGX_HTTP_ACCESS_PHASE
        P->>P: NGX_HTTP_POST_ACCESS_PHASE
        P->>P: NGX_HTTP_PRECONTENT_PHASE
        P->>P: NGX_HTTP_CONTENT_PHASE
    end
    
    alt Static Content
        P->>F: Generate static content
    else Proxy Request
        P->>U: ngx_http_proxy_handler()
        U->>U: Create upstream connection
        U->>U: Send request to backend
        U->>U: Receive response from backend
        U-->>P: Return response
    end
    
    P->>F: ngx_http_send_header()
    F->>F: Header filter chain
    P->>F: ngx_http_output_filter()
    F->>F: Body filter chain
    
    F->>W: Send response
    W->>C: HTTP Response
    
    W->>H: ngx_http_finalize_request()
    H->>H: Cleanup request
    
    alt Keep-Alive
        H->>H: ngx_http_set_keepalive()
    else Close Connection
        H->>E: ngx_http_close_connection()
    end

4.2 HTTP阶段处理详细时序

sequenceDiagram
    participant R as Request
    participant PE as Phase Engine
    participant RW as Rewrite Module
    participant AC as Access Module
    participant CT as Content Module
    participant LG as Log Module

    R->>PE: ngx_http_core_run_phases()
    
    PE->>PE: POST_READ_PHASE
    Note over PE: Read request body if needed
    
    PE->>RW: SERVER_REWRITE_PHASE
    RW->>RW: Server-level rewrite rules
    RW-->>PE: Continue/Redirect
    
    PE->>PE: FIND_CONFIG_PHASE
    Note over PE: Find location configuration
    
    PE->>RW: REWRITE_PHASE
    RW->>RW: Location-level rewrite rules
    RW-->>PE: Continue/Redirect
    
    PE->>PE: POST_REWRITE_PHASE
    Note over PE: Handle rewrite results
    
    PE->>AC: PREACCESS_PHASE
    AC->>AC: Rate limiting, etc.
    AC-->>PE: Allow/Deny
    
    PE->>AC: ACCESS_PHASE
    AC->>AC: Access control checks
    AC-->>PE: Allow/Deny
    
    PE->>PE: POST_ACCESS_PHASE
    Note over PE: Handle access results
    
    PE->>PE: PRECONTENT_PHASE
    Note over PE: Pre-content processing
    
    PE->>CT: CONTENT_PHASE
    CT->>CT: Generate content
    CT-->>PE: Content generated
    
    PE->>LG: LOG_PHASE
    LG->>LG: Log request
    LG-->>PE: Logged

5. 事件处理架构图

5.1 事件循环架构

graph TB
    subgraph "Event Loop"
        EL[Event Loop<br/>ngx_process_events_and_timers]
    end
    
    subgraph "Event Sources"
        NE[Network Events<br/>- Accept<br/>- Read<br/>- Write]
        TE[Timer Events<br/>- Connection timeout<br/>- Request timeout<br/>- Keepalive timeout]
        SE[Signal Events<br/>- SIGTERM<br/>- SIGHUP<br/>- SIGUSR1]
    end
    
    subgraph "Event Methods"
        EP[Epoll<br/>Linux]
        KQ[Kqueue<br/>BSD/macOS]
        SEL[Select<br/>Fallback]
    end
    
    subgraph "Event Handlers"
        AH[Accept Handler<br/>ngx_event_accept]
        RH[Read Handler<br/>ngx_http_request_handler]
        WH[Write Handler<br/>ngx_http_request_handler]
        TH[Timer Handler<br/>Various timeout handlers]
    end
    
    NE --> EL
    TE --> EL
    SE --> EL
    
    EL --> EP
    EL --> KQ
    EL --> SEL
    
    EP --> AH
    EP --> RH
    EP --> WH
    KQ --> AH
    KQ --> RH
    KQ --> WH
    SEL --> AH
    SEL --> RH
    SEL --> WH
    
    TE --> TH

5.2 连接处理流程图

graph TB
    subgraph "Connection Lifecycle"
        A[Accept Connection] --> B[Initialize Connection]
        B --> C[Read Request]
        C --> D[Process Request]
        D --> E[Send Response]
        E --> F{Keep-Alive?}
        F -->|Yes| G[Set Keepalive Timer]
        F -->|No| H[Close Connection]
        G --> C
        H --> I[Free Resources]
    end
    
    subgraph "Connection Pool"
        CP[Connection Pool<br/>- Free connections<br/>- Active connections<br/>- Connection reuse]
    end
    
    subgraph "Event Management"
        EM[Event Management<br/>- Add events<br/>- Delete events<br/>- Modify events]
    end
    
    A -.-> CP
    B -.-> EM
    C -.-> EM
    E -.-> EM
    H -.-> CP
    I -.-> CP

6. 内存管理架构图

6.1 内存池架构

graph TB
    subgraph "Memory Pool Hierarchy"
        GP[Global Pool<br/>ngx_cycle->pool]
        CP[Connection Pool<br/>c->pool]
        RP[Request Pool<br/>r->pool]
        TP[Temp Pool<br/>Temporary allocations]
    end
    
    subgraph "Pool Structure"
        PD[Pool Data<br/>- last<br/>- end<br/>- next<br/>- failed]
        PL[Large Blocks<br/>- size > max<br/>- Direct allocation]
        PC[Cleanup Handlers<br/>- File cleanup<br/>- Memory cleanup]
    end
    
    subgraph "Allocation Types"
        SA[Small Allocation<br/>size <= max<br/>From pool blocks]
        LA[Large Allocation<br/>size > max<br/>Direct malloc]
        AA[Aligned Allocation<br/>Memory alignment<br/>Performance optimization]
    end
    
    GP --> CP
    CP --> RP
    RP --> TP
    
    CP --> PD
    CP --> PL
    CP --> PC
    
    PD --> SA
    PL --> LA
    SA --> AA

6.2 缓冲区管理架构

graph TB
    subgraph "Buffer Types"
        TB[Temp Buffer<br/>- Temporary data<br/>- Request processing]
        FB[File Buffer<br/>- File content<br/>- Static files]
        MB[Memory Buffer<br/>- Dynamic content<br/>- Generated data]
        CB[Chain Buffer<br/>- Linked buffers<br/>- Large content]
    end
    
    subgraph "Buffer Operations"
        BA[Buffer Allocation<br/>ngx_create_temp_buf]
        BC[Buffer Copy<br/>ngx_copy_buf]
        BM[Buffer Move<br/>ngx_move_buf]
        BF[Buffer Free<br/>Pool cleanup]
    end
    
    subgraph "Buffer Chain"
        CH[Chain Head<br/>First buffer]
        CN[Chain Node<br/>Buffer + next]
        CT[Chain Tail<br/>Last buffer]
    end
    
    TB --> BA
    FB --> BA
    MB --> BA
    CB --> BA
    
    BA --> BC
    BC --> BM
    BM --> BF
    
    CH --> CN
    CN --> CT
    CB --> CH

7. 配置系统架构图

7.1 配置解析架构

graph TB
    subgraph "Configuration Files"
        MC[Main Config<br/>nginx.conf]
        IC[Include Configs<br/>conf.d/*.conf]
        MC --> IC
    end
    
    subgraph "Parser Components"
        L[Lexer<br/>Token generation]
        P[Parser<br/>Syntax analysis]
        H[Handler<br/>Directive processing]
    end
    
    subgraph "Configuration Context"
        MAIN[Main Context<br/>Global settings]
        HTTP[HTTP Context<br/>HTTP settings]
        SERVER[Server Context<br/>Virtual host settings]
        LOCATION[Location Context<br/>URI-specific settings]
    end
    
    subgraph "Module Configs"
        CC[Core Config<br/>ngx_core_conf_t]
        HC[HTTP Config<br/>ngx_http_core_conf_t]
        SC[Server Config<br/>Server-specific]
        LC[Location Config<br/>Location-specific]
    end
    
    MC --> L
    L --> P
    P --> H
    
    H --> MAIN
    MAIN --> HTTP
    HTTP --> SERVER
    SERVER --> LOCATION
    
    MAIN --> CC
    HTTP --> HC
    SERVER --> SC
    LOCATION --> LC

7.2 指令处理流程图

graph TB
    subgraph "Directive Processing"
        A[Read Directive] --> B[Find Command]
        B --> C{Command Found?}
        C -->|No| D[Unknown Directive Error]
        C -->|Yes| E[Check Context]
        E --> F{Valid Context?}
        F -->|No| G[Context Error]
        F -->|Yes| H[Check Arguments]
        H --> I{Valid Arguments?}
        I -->|No| J[Argument Error]
        I -->|Yes| K[Call Handler]
        K --> L[Update Configuration]
        L --> M[Continue Parsing]
    end
    
    subgraph "Command Structure"
        CS[ngx_command_t<br/>- name<br/>- type<br/>- set function<br/>- conf offset]
    end
    
    subgraph "Context Types"
        CT[Context Types<br/>- NGX_MAIN_CONF<br/>- NGX_HTTP_MAIN_CONF<br/>- NGX_HTTP_SRV_CONF<br/>- NGX_HTTP_LOC_CONF]
    end
    
    B -.-> CS
    E -.-> CT

8. 模块交互图

8.1 HTTP模块交互

graph TB
    subgraph "HTTP Request Flow"
        HC[HTTP Core] --> HR[HTTP Rewrite]
        HR --> HA[HTTP Access]
        HA --> HCT[HTTP Content]
        HCT --> HF[HTTP Filter]
    end
    
    subgraph "Filter Chain"
        HHF[Header Filter Chain]
        HBF[Body Filter Chain]
        
        HHF --> HBF
    end
    
    subgraph "Content Handlers"
        HS[Static Handler]
        HP[Proxy Handler]
        HFC[FastCGI Handler]
        HI[Index Handler]
    end
    
    subgraph "Access Modules"
        HAC[Access Control]
        HAL[Auth Basic]
        HAR[Auth Request]
        HRL[Rate Limit]
    end
    
    HCT --> HS
    HCT --> HP
    HCT --> HFC
    HCT --> HI
    
    HA --> HAC
    HA --> HAL
    HA --> HAR
    HA --> HRL
    
    HF --> HHF
    HF --> HBF

8.2 事件模块交互

graph TB
    subgraph "Event Core"
        EC[Event Core<br/>ngx_event_core_module]
    end
    
    subgraph "Event Methods"
        EE[Epoll Module<br/>Linux specific]
        EK[Kqueue Module<br/>BSD/macOS specific]
        ES[Select Module<br/>Universal fallback]
        EP[Poll Module<br/>POSIX systems]
    end
    
    subgraph "Event Actions"
        EA[Event Actions<br/>- Add event<br/>- Delete event<br/>- Enable event<br/>- Disable event]
    end
    
    subgraph "Timer Management"
        TM[Timer Management<br/>- Add timer<br/>- Delete timer<br/>- Process timers]
    end
    
    EC --> EE
    EC --> EK
    EC --> ES
    EC --> EP
    
    EE --> EA
    EK --> EA
    ES --> EA
    EP --> EA
    
    EC --> TM

9. 负载均衡架构图

9.1 上游服务器架构

graph TB
    subgraph "Upstream Configuration"
        UC[Upstream Config<br/>upstream backend]
        S1[Server 1<br/>192.168.1.10:80]
        S2[Server 2<br/>192.168.1.11:80]
        S3[Server 3<br/>192.168.1.12:80]
        
        UC --> S1
        UC --> S2
        UC --> S3
    end
    
    subgraph "Load Balancing Methods"
        RR[Round Robin<br/>Default method]
        WRR[Weighted Round Robin<br/>Weight-based]
        LF[Least Connections<br/>Connection-based]
        IPH[IP Hash<br/>Client IP based]
        H[Hash<br/>Custom key based]
    end
    
    subgraph "Health Checking"
        HC[Health Check<br/>- Active checks<br/>- Passive checks<br/>- Failure detection]
        FB[Failover<br/>- Backup servers<br/>- Automatic failover<br/>- Recovery detection]
    end
    
    subgraph "Connection Management"
        CP[Connection Pool<br/>- Persistent connections<br/>- Connection reuse<br/>- Connection limits]
        KA[Keep-Alive<br/>- Upstream keep-alive<br/>- Connection timeout<br/>- Request pipelining]
    end
    
    UC --> RR
    UC --> WRR
    UC --> LF
    UC --> IPH
    UC --> H
    
    S1 -.-> HC
    S2 -.-> HC
    S3 -.-> HC
    
    HC --> FB
    
    UC --> CP
    CP --> KA

9.2 代理请求流程图

sequenceDiagram
    participant C as Client
    participant N as Nginx
    participant U as Upstream
    participant B as Backend

    C->>N: HTTP Request
    N->>N: Select upstream server
    N->>U: Create upstream connection
    U->>B: Connect to backend
    B-->>U: Connection established
    
    N->>U: Send request headers
    U->>B: Forward headers
    
    alt Request has body
        N->>U: Send request body
        U->>B: Forward body
    end
    
    B->>U: Response headers
    U->>N: Forward headers
    N->>C: Send response headers
    
    loop Response body
        B->>U: Response body chunk
        U->>N: Forward chunk
        N->>C: Send chunk
    end
    
    B->>U: End of response
    U->>N: Response complete
    N->>C: Complete response
    
    alt Keep-alive upstream
        U->>U: Keep connection alive
    else Close upstream
        U->>B: Close connection
    end
    
    alt Keep-alive client
        N->>N: Keep connection alive
    else Close client
        N->>C: Close connection
    end

10. 缓存系统架构图

10.1 缓存层次架构

graph TB
    subgraph "Cache Hierarchy"
        L1[L1 Cache<br/>Memory Cache<br/>Hot data]
        L2[L2 Cache<br/>Disk Cache<br/>Warm data]
        L3[L3 Cache<br/>Remote Cache<br/>Cold data]
    end
    
    subgraph "Cache Types"
        PC[Proxy Cache<br/>Upstream responses]
        FC[FastCGI Cache<br/>FastCGI responses]
        SC[Static Cache<br/>Static files]
        MC[Micro Cache<br/>Short-term cache]
    end
    
    subgraph "Cache Management"
        CM[Cache Manager<br/>- Cache maintenance<br/>- Memory management<br/>- Disk cleanup]
        CL[Cache Loader<br/>- Cache initialization<br/>- Metadata loading<br/>- Index building]
        CI[Cache Invalidation<br/>- TTL expiration<br/>- Manual purge<br/>- Conditional refresh]
    end
    
    subgraph "Storage Backend"
        MEM[Memory Storage<br/>- Shared memory<br/>- Fast access<br/>- Limited size]
        DISK[Disk Storage<br/>- File system<br/>- Large capacity<br/>- Persistent]
    end
    
    L1 --> L2
    L2 --> L3
    
    PC --> L1
    FC --> L1
    SC --> L2
    MC --> L1
    
    L1 --> MEM
    L2 --> DISK
    
    CM --> MEM
    CM --> DISK
    CL --> DISK
    CI --> MEM
    CI --> DISK

10.2 缓存处理流程图

graph TB
    A[Incoming Request] --> B{Cache Enabled?}
    B -->|No| C[Process Normally]
    B -->|Yes| D[Generate Cache Key]
    D --> E{Cache Hit?}
    E -->|Yes| F{Cache Valid?}
    E -->|No| G[Fetch from Origin]
    F -->|Yes| H[Serve from Cache]
    F -->|No| I[Conditional Request]
    I --> J{304 Not Modified?}
    J -->|Yes| K[Update Cache Metadata]
    J -->|No| L[Update Cache Content]
    G --> M[Store in Cache]
    M --> N[Serve Response]
    H --> O[Update Access Time]
    K --> H
    L --> N
    C --> N
    O --> P[End]
    N --> P

11. SSL/TLS架构图

11.1 SSL处理架构

graph TB
    subgraph "SSL/TLS Layer"
        SSL[SSL Module<br/>ngx_http_ssl_module]
        TLS[TLS Implementation<br/>OpenSSL/BoringSSL]
    end
    
    subgraph "Certificate Management"
        CERT[Certificate Storage<br/>- Server certificates<br/>- CA certificates<br/>- Certificate chains]
        SNI[SNI Support<br/>- Multiple certificates<br/>- Dynamic selection<br/>- Wildcard support]
        OCSP[OCSP Stapling<br/>- Certificate validation<br/>- Performance optimization<br/>- Security enhancement]
    end
    
    subgraph "Cipher Management"
        CS[Cipher Suites<br/>- Supported ciphers<br/>- Security preferences<br/>- Performance tuning]
        DH[Diffie-Hellman<br/>- Key exchange<br/>- Perfect forward secrecy<br/>- Custom parameters]
        ECDH[ECDH Support<br/>- Elliptic curve<br/>- Modern cryptography<br/>- Better performance]
    end
    
    subgraph "Session Management"
        SC[Session Cache<br/>- Session reuse<br/>- Memory efficiency<br/>- Performance boost]
        ST[Session Tickets<br/>- Stateless resumption<br/>- Scalability<br/>- Load balancing]
    end
    
    SSL --> TLS
    SSL --> CERT
    SSL --> CS
    SSL --> SC
    
    CERT --> SNI
    CERT --> OCSP
    
    CS --> DH
    CS --> ECDH
    
    SC --> ST

11.2 SSL握手时序图

sequenceDiagram
    participant C as Client
    participant N as Nginx
    participant SSL as SSL Engine

    C->>N: TCP Connection
    C->>N: ClientHello
    N->>SSL: Process ClientHello
    SSL->>SSL: Select cipher suite
    SSL->>SSL: Load certificate
    SSL-->>N: ServerHello + Certificate
    N->>C: ServerHello + Certificate
    
    C->>C: Verify certificate
    C->>N: ClientKeyExchange
    N->>SSL: Process key exchange
    SSL->>SSL: Generate session keys
    
    C->>N: ChangeCipherSpec + Finished
    N->>SSL: Verify finished message
    SSL-->>N: Session established
    N->>C: ChangeCipherSpec + Finished
    
    Note over C,N: Encrypted communication begins
    
    C->>N: Encrypted HTTP Request
    N->>SSL: Decrypt request
    SSL-->>N: Decrypted data
    N->>N: Process HTTP request
    N->>SSL: Encrypt response
    SSL-->>N: Encrypted data
    N->>C: Encrypted HTTP Response

12. 监控和统计架构图

12.1 统计收集架构

graph TB
    subgraph "Statistics Collection"
        SC[Statistics Collector<br/>- Request counters<br/>- Response times<br/>- Error rates]
        SM[Shared Memory<br/>- Cross-process stats<br/>- Atomic operations<br/>- Lock-free updates]
    end
    
    subgraph "Metrics Types"
        RM[Request Metrics<br/>- Total requests<br/>- Requests per second<br/>- Request size]
        CM[Connection Metrics<br/>- Active connections<br/>- Connection rate<br/>- Connection duration]
        UM[Upstream Metrics<br/>- Backend status<br/>- Response times<br/>- Failure rates]
        EM[Error Metrics<br/>- HTTP errors<br/>- SSL errors<br/>- Timeout errors]
    end
    
    subgraph "Export Formats"
        JSON[JSON Format<br/>- REST API<br/>- Machine readable<br/>- Integration friendly]
        PROM[Prometheus Format<br/>- Time series<br/>- Monitoring systems<br/>- Alerting support]
        LOG[Log Format<br/>- Access logs<br/>- Error logs<br/>- Custom formats]
    end
    
    SC --> SM
    
    SC --> RM
    SC --> CM
    SC --> UM
    SC --> EM
    
    SM --> JSON
    SM --> PROM
    SM --> LOG

12.2 健康检查架构

graph TB
    subgraph "Health Check Types"
        AC[Active Checks<br/>- Periodic probes<br/>- Custom endpoints<br/>- Configurable intervals]
        PC[Passive Checks<br/>- Request monitoring<br/>- Error detection<br/>- Automatic marking]
    end
    
    subgraph "Check Methods"
        HTTP[HTTP Checks<br/>- GET/POST requests<br/>- Status code validation<br/>- Response content check]
        TCP[TCP Checks<br/>- Connection test<br/>- Port availability<br/>- Network reachability]
        CUSTOM[Custom Checks<br/>- Script execution<br/>- External tools<br/>- Complex validation]
    end
    
    subgraph "Failure Handling"
        FD[Failure Detection<br/>- Threshold-based<br/>- Consecutive failures<br/>- Time-based windows]
        FB[Failover Logic<br/>- Server marking<br/>- Traffic redirection<br/>- Backup activation]
        REC[Recovery Detection<br/>- Health restoration<br/>- Gradual traffic increase<br/>- Monitoring period]
    end
    
    AC --> HTTP
    AC --> TCP
    AC --> CUSTOM
    
    PC --> FD
    AC --> FD
    
    FD --> FB
    FB --> REC

13. 总结

Nginx的架构设计体现了以下核心特点：

13.1 设计原则

模块化: 高度模块化的设计，功能解耦
事件驱动: 异步非阻塞的事件处理模型
多进程: Master-Worker进程模型，稳定可靠
内存高效: 内存池管理，减少内存碎片
配置驱动: 灵活的配置系统，运行时可重载

13.2 性能特点

高并发: 单个Worker可处理数万并发连接
低内存: 高效的内存管理和数据结构
零拷贝: 减少数据复制，提高性能
缓存友好: 多层缓存架构，提升响应速度
负载均衡: 多种负载均衡算法，高可用性

13.3 扩展性

插件架构: 支持第三方模块开发
动态加载: 运行时加载模块
配置热更新: 无缝配置重载
API友好: 丰富的开发接口
跨平台: 支持多种操作系统

通过这些架构图和时序图，开发者可以更好地理解Nginx的内部工作机制，为深入学习和扩展Nginx功能打下坚实基础。

Nginx 整体架构图和时序图#

1. 概述#

2. 整体架构图#

2.1 系统层次架构#

2.2 进程架构图#

2.3 模块架构图#

3. 启动时序图#

3.1 Master进程启动时序#

3.2 Worker进程启动时序#

4. HTTP请求处理时序图#

4.1 完整HTTP请求处理流程#

4.2 HTTP阶段处理详细时序#

5. 事件处理架构图#

5.1 事件循环架构#

5.2 连接处理流程图#

6. 内存管理架构图#

6.1 内存池架构#

6.2 缓冲区管理架构#

7. 配置系统架构图#

7.1 配置解析架构#

7.2 指令处理流程图#

8. 模块交互图#

8.1 HTTP模块交互#

8.2 事件模块交互#

9. 负载均衡架构图#

9.1 上游服务器架构#

9.2 代理请求流程图#

10. 缓存系统架构图#

10.1 缓存层次架构#

10.2 缓存处理流程图#

11. SSL/TLS架构图#

11.1 SSL处理架构#

11.2 SSL握手时序图#

12. 监控和统计架构图#

12.1 统计收集架构#

12.2 健康检查架构#

13. 总结#

13.1 设计原则#

13.2 性能特点#

13.3 扩展性#

Nginx 整体架构图和时序图

1. 概述

2. 整体架构图

2.1 系统层次架构

2.2 进程架构图

2.3 模块架构图

3. 启动时序图

3.1 Master进程启动时序

3.2 Worker进程启动时序

4. HTTP请求处理时序图

4.1 完整HTTP请求处理流程

4.2 HTTP阶段处理详细时序

5. 事件处理架构图

5.1 事件循环架构

5.2 连接处理流程图

6. 内存管理架构图

6.1 内存池架构

6.2 缓冲区管理架构

7. 配置系统架构图

7.1 配置解析架构

7.2 指令处理流程图

8. 模块交互图

8.1 HTTP模块交互

8.2 事件模块交互

9. 负载均衡架构图

9.1 上游服务器架构

9.2 代理请求流程图

10. 缓存系统架构图

10.1 缓存层次架构

10.2 缓存处理流程图

11. SSL/TLS架构图

11.1 SSL处理架构

11.2 SSL握手时序图

12. 监控和统计架构图

12.1 统计收集架构

12.2 健康检查架构

13. 总结

13.1 设计原则

13.2 性能特点

13.3 扩展性