view src/os/unix/ngx_os.h @ 7985:ec2e6893caaa

Simplified sendfile(SF_NODISKIO) usage. Starting with FreeBSD 11, there is no need to use AIO operations to preload data into cache for sendfile(SF_NODISKIO) to work. Instead, sendfile() handles non-blocking loading data from disk by itself. It still can, however, return EBUSY if a page is already being loaded (for example, by a different process). If this happens, we now post an event for the next event loop iteration, so sendfile() is retried "after a short period", as manpage recommends. The limit of the number of EBUSY tolerated without any progress is preserved, but now it does not result in an alert, since on an idle system event loop iteration might be very short and EBUSY can happen many times in a row. Instead, SF_NODISKIO is simply disabled for one call once the limit is reached. With this change, sendfile(SF_NODISKIO) is now used automatically as long as sendfile() is enabled, and no longer requires "aio on;".
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 27 Dec 2021 19:48:33 +0300
parents 56fc55e32f23
children 3d455e37abf8
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_OS_H_INCLUDED_
#define _NGX_OS_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


#define NGX_IO_SENDFILE    1


typedef ssize_t (*ngx_recv_pt)(ngx_connection_t *c, u_char *buf, size_t size);
typedef ssize_t (*ngx_recv_chain_pt)(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);
typedef ssize_t (*ngx_send_pt)(ngx_connection_t *c, u_char *buf, size_t size);
typedef ngx_chain_t *(*ngx_send_chain_pt)(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);

typedef struct {
    ngx_recv_pt        recv;
    ngx_recv_chain_pt  recv_chain;
    ngx_recv_pt        udp_recv;
    ngx_send_pt        send;
    ngx_send_pt        udp_send;
    ngx_send_chain_pt  udp_send_chain;
    ngx_send_chain_pt  send_chain;
    ngx_uint_t         flags;
} ngx_os_io_t;


ngx_int_t ngx_os_init(ngx_log_t *log);
void ngx_os_status(ngx_log_t *log);
ngx_int_t ngx_os_specific_init(ngx_log_t *log);
void ngx_os_specific_status(ngx_log_t *log);
ngx_int_t ngx_daemon(ngx_log_t *log);
ngx_int_t ngx_os_signal_process(ngx_cycle_t *cycle, char *sig, ngx_pid_t pid);


ssize_t ngx_unix_recv(ngx_connection_t *c, u_char *buf, size_t size);
ssize_t ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *entry, off_t limit);
ssize_t ngx_udp_unix_recv(ngx_connection_t *c, u_char *buf, size_t size);
ssize_t ngx_unix_send(ngx_connection_t *c, u_char *buf, size_t size);
ngx_chain_t *ngx_writev_chain(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);
ssize_t ngx_udp_unix_send(ngx_connection_t *c, u_char *buf, size_t size);
ngx_chain_t *ngx_udp_unix_sendmsg_chain(ngx_connection_t *c, ngx_chain_t *in,
    off_t limit);


#if (IOV_MAX > 64)
#define NGX_IOVS_PREALLOCATE  64
#else
#define NGX_IOVS_PREALLOCATE  IOV_MAX
#endif


typedef struct {
    struct iovec  *iovs;
    ngx_uint_t     count;
    size_t         size;
    ngx_uint_t     nalloc;
} ngx_iovec_t;

ngx_chain_t *ngx_output_chain_to_iovec(ngx_iovec_t *vec, ngx_chain_t *in,
    size_t limit, ngx_log_t *log);


ssize_t ngx_writev(ngx_connection_t *c, ngx_iovec_t *vec);


extern ngx_os_io_t  ngx_os_io;
extern ngx_int_t    ngx_ncpu;
extern ngx_int_t    ngx_max_sockets;
extern ngx_uint_t   ngx_inherited_nonblocking;
extern ngx_uint_t   ngx_tcp_nodelay_and_tcp_nopush;


#if (NGX_FREEBSD)
#include <ngx_freebsd.h>


#elif (NGX_LINUX)
#include <ngx_linux.h>


#elif (NGX_SOLARIS)
#include <ngx_solaris.h>


#elif (NGX_DARWIN)
#include <ngx_darwin.h>
#endif


#endif /* _NGX_OS_H_INCLUDED_ */