三、Redis主存储

3.1、存储相关结构体

redisServer：服务器

server.h

struct redisServer {
    /* General */
    pid_t pid;                  /* Main process pid. */
    pthread_t main_thread_id;         /* Main thread id */
    char *configfile;           /* Absolute config file path, or NULL */
    char *executable;           /* Absolute executable file path. */
    char **exec_argv;           /* Executable argv vector (copy). */
    int dynamic_hz;             /* Change hz value depending on # of clients. */
    int config_hz;              /* Configured HZ value. May be different than
                                   the actual 'hz' field value if dynamic-hz
                                   is enabled. */
    mode_t umask;               /* The umask value of the process on startup */
    int hz;                     /* serverCron() calls frequency in hertz */
    int in_fork_child;          /* indication that this is a fork child */
    redisDb *db;
    dict *commands;             /* Command table */
    dict *orig_commands;        /* Command table before command renaming. */
    aeEventLoop *el;
    rax *errors;                /* Errors table */
    redisAtomic unsigned int lruclock; /* Clock for LRU eviction */
    volatile sig_atomic_t shutdown_asap; /* SHUTDOWN needed ASAP */
    int activerehashing;        /* Incremental rehash in serverCron() */
    int active_defrag_running;  /* Active defragmentation running (holds current scan aggressiveness) */
    char *pidfile;              /* PID file path */
    int arch_bits;              /* 32 or 64 depending on sizeof(long) */
    int cronloops;              /* Number of times the cron function run */
    char runid[CONFIG_RUN_ID_SIZE+1];  /* ID always different at every exec. */
    int sentinel_mode;          /* True if this instance is a Sentinel. */
    size_t initial_memory_usage; /* Bytes used after initialization. */
    int always_show_logo;       /* Show logo even for non-stdout logging. */
    int in_eval;                /* Are we inside EVAL? */
    int in_exec;                /* Are we inside EXEC? */
    int propagate_in_transaction;  /* Make sure we don't propagate nested MULTI/EXEC */
    char *ignore_warnings;      /* Config: warnings that should be ignored. */
    int client_pause_in_transaction; /* Was a client pause executed during this Exec? */
    /* Modules */
    dict *moduleapi;            /* Exported core APIs dictionary for modules. */
    dict *sharedapi;            /* Like moduleapi but containing the APIs that
                                   modules share with each other. */
    list *loadmodule_queue;     /* List of modules to load at startup. */
    int module_blocked_pipe[2]; /* Pipe used to awake the event loop if a
                                   client blocked on a module command needs
                                   to be processed. */
    pid_t child_pid;            /* PID of current child */
    int child_type;             /* Type of current child */
    client *module_client;      /* "Fake" client to call Redis from modules */
    /* Networking */
    int port;                   /* TCP listening port */
    int tls_port;               /* TLS listening port */
    int tcp_backlog;            /* TCP listen() backlog */
    char *bindaddr[CONFIG_BINDADDR_MAX]; /* Addresses we should bind to */
    int bindaddr_count;         /* Number of addresses in server.bindaddr[] */
    char *unixsocket;           /* UNIX socket path */
    mode_t unixsocketperm;      /* UNIX socket permission */
    socketFds ipfd;             /* TCP socket file descriptors */
    socketFds tlsfd;            /* TLS socket file descriptors */
    int sofd;                   /* Unix socket file descriptor */
    socketFds cfd;              /* Cluster bus listening socket */
    list *clients;              /* List of active clients */
    list *clients_to_close;     /* Clients to close asynchronously */
    list *clients_pending_write; /* There is to write or install handler. */
    list *clients_pending_read;  /* Client has pending read socket buffers. */
    list *slaves, *monitors;    /* List of slaves and MONITORs */
    client *current_client;     /* Current client executing the command. */
    rax *clients_timeout_table; /* Radix tree for blocked clients timeouts. */
    long fixed_time_expire;     /* If > 0, expire keys against server.mstime. */
    rax *clients_index;         /* Active clients dictionary by client ID. */
    pause_type client_pause_type;      /* True if clients are currently paused */
    list *paused_clients;       /* List of pause clients */
    mstime_t client_pause_end_time;    /* Time when we undo clients_paused */
    char neterr[ANET_ERR_LEN];   /* Error buffer for anet.c */
    dict *migrate_cached_sockets;/* MIGRATE cached sockets */
    redisAtomic uint64_t next_client_id; /* Next client unique ID. Incremental. */
    int protected_mode;         /* Don't accept external connections. */
    int gopher_enabled;         /* If true the server will reply to gopher
                                   queries. Will still serve RESP2 queries. */
    int io_threads_num;         /* Number of IO threads to use. */
    int io_threads_do_reads;    /* Read and parse from IO threads? */
    int io_threads_active;      /* Is IO threads currently active? */
    long long events_processed_while_blocked; /* processEventsWhileBlocked() */
​
    /* RDB / AOF loading information */
    volatile sig_atomic_t loading; /* We are loading data from disk if true */
    off_t loading_total_bytes;
    off_t loading_rdb_used_mem;
    off_t loading_loaded_bytes;
    time_t loading_start_time;
    off_t loading_process_events_interval_bytes;
    /* Fast pointers to often looked up command */
    struct redisCommand *delCommand, *multiCommand, *lpushCommand,
                        *lpopCommand, *rpopCommand, *zpopminCommand,
                        *zpopmaxCommand, *sremCommand, *execCommand,
                        *expireCommand, *pexpireCommand, *xclaimCommand,
                        *xgroupCommand, *rpoplpushCommand, *lmoveCommand;
    /* Fields used only for stats */
    time_t stat_starttime;          /* Server start time */
    long long stat_numcommands;     /* Number of processed commands */
    long long stat_numconnections;  /* Number of connections received */
    long long stat_expiredkeys;     /* Number of expired keys */
    double stat_expired_stale_perc; /* Percentage of keys probably expired */
    long long stat_expired_time_cap_reached_count; /* Early expire cylce stops.*/
    long long stat_expire_cycle_time_used; /* Cumulative microseconds used. */
    long long stat_evictedkeys;     /* Number of evicted keys (maxmemory) */
    long long stat_keyspace_hits;   /* Number of successful lookups of keys */
    long long stat_keyspace_misses; /* Number of failed lookups of keys */
    long long stat_active_defrag_hits;      /* number of allocations moved */
    long long stat_active_defrag_misses;    /* number of allocations scanned but not moved */
    long long stat_active_defrag_key_hits;  /* number of keys with moved allocations */
    long long stat_active_defrag_key_misses;/* number of keys scanned and not moved */
    long long stat_active_defrag_scanned;   /* number of dictEntries scanned */
    size_t stat_peak_memory;        /* Max used memory record */
    long long stat_fork_time;       /* Time needed to perform latest fork() */
    double stat_fork_rate;          /* Fork rate in GB/sec. */
    long long stat_total_forks;     /* Total count of fork. */
    long long stat_rejected_conn;   /* Clients rejected because of maxclients */
    long long stat_sync_full;       /* Number of full resyncs with slaves. */
    long long stat_sync_partial_ok; /* Number of accepted PSYNC requests. */
    long long stat_sync_partial_err;/* Number of unaccepted PSYNC requests. */
    list *slowlog;                  /* SLOWLOG list of commands */
    long long slowlog_entry_id;     /* SLOWLOG current entry ID */
    long long slowlog_log_slower_than; /* SLOWLOG time limit (to get logged) */
    unsigned long slowlog_max_len;     /* SLOWLOG max number of items logged */
    struct malloc_stats cron_malloc_stats; /* sampled in serverCron(). */
    redisAtomic long long stat_net_input_bytes; /* Bytes read from network. */
    redisAtomic long long stat_net_output_bytes; /* Bytes written to network. */
    size_t stat_current_cow_bytes;  /* Copy on write bytes while child is active. */
    monotime stat_current_cow_updated;  /* Last update time of stat_current_cow_bytes */
    size_t stat_current_save_keys_processed;  /* Processed keys while child is active. */
    size_t stat_current_save_keys_total;  /* Number of keys when child started. */
    size_t stat_rdb_cow_bytes;      /* Copy on write bytes during RDB saving. */