Mercurial > hg > nginx
view src/core/ngx_slab.h @ 8078:5244d3b165ff
SSL: single allocation in session cache on 32-bit platforms.
Given the present typical SSL session sizes, on 32-bit platforms it is
now beneficial to store all data in a single allocation, since rbtree
node + session id + ASN1 representation of a session takes 256 bytes of
shared memory (36 + 32 + 150 = about 218 bytes plus SNI server name).
Storing all data in a single allocation is beneficial for SNI names up to
about 40 characters long and makes it possible to store about 4000 sessions
in one megabyte (instead of about 3000 sessions now). This also slightly
simplifies the code.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 12 Oct 2022 20:14:40 +0300 |
parents | 69f9ee0342db |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_SLAB_H_INCLUDED_ #define _NGX_SLAB_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> typedef struct ngx_slab_page_s ngx_slab_page_t; struct ngx_slab_page_s { uintptr_t slab; ngx_slab_page_t *next; uintptr_t prev; }; typedef struct { ngx_uint_t total; ngx_uint_t used; ngx_uint_t reqs; ngx_uint_t fails; } ngx_slab_stat_t; typedef struct { ngx_shmtx_sh_t lock; size_t min_size; size_t min_shift; ngx_slab_page_t *pages; ngx_slab_page_t *last; ngx_slab_page_t free; ngx_slab_stat_t *stats; ngx_uint_t pfree; u_char *start; u_char *end; ngx_shmtx_t mutex; u_char *log_ctx; u_char zero; unsigned log_nomem:1; void *data; void *addr; } ngx_slab_pool_t; void ngx_slab_sizes_init(void); void ngx_slab_init(ngx_slab_pool_t *pool); void *ngx_slab_alloc(ngx_slab_pool_t *pool, size_t size); void *ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size); void *ngx_slab_calloc(ngx_slab_pool_t *pool, size_t size); void *ngx_slab_calloc_locked(ngx_slab_pool_t *pool, size_t size); void ngx_slab_free(ngx_slab_pool_t *pool, void *p); void ngx_slab_free_locked(ngx_slab_pool_t *pool, void *p); #endif /* _NGX_SLAB_H_INCLUDED_ */