Core: slab allocator free pages defragmentation. Large allocations from a slab pool result in free page blocks being fragmented, eventually leading to a situation when no further allocation larger than a page size are possible from the pool. While this isn't a problem for nginx itself, it is known to be bad for various 3rd party modules. Fix is to merge adjacent blocks of free pages in the ngx_slab_free_pages() function. Prodded by Wandenberg Peixoto and Yichun Zhang.

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


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


int
ngx_nonblocking(ngx_socket_t s)
{
    unsigned long  nb = 1;

    return ioctlsocket(s, FIONBIO, &nb);
}


int
ngx_blocking(ngx_socket_t s)
{
    unsigned long  nb = 0;

    return ioctlsocket(s, FIONBIO, &nb);
}


int
ngx_tcp_push(ngx_socket_t s)
{
    return 0;
}