Mercurial > hg > nginx-quic
view src/core/ngx_times.h @ 4385:70ba81827472
Cache locks initial implementation.
New directives: proxy_cache_lock on/off, proxy_cache_lock_timeout. With
proxy_cache_lock set to on, only one request will be allowed to go to
upstream for a particular cache item. Others will wait for a response
to appear in cache (or cache lock released) up to proxy_cache_lock_timeout.
Waiting requests will recheck if they have cached response ready (or are
allowed to run) every 500ms.
Note: we intentionally don't intercept NGX_DECLINED possibly returned by
ngx_http_file_cache_read(). This needs more work (possibly safe, but needs
further investigation). Anyway, it's exceptional situation.
Note: probably there should be a way to disable caching of responses
if there is already one request fetching resource to cache (without waiting
at all). Two possible ways include another cache lock option ("no_cache")
or using proxy_no_cache with some supplied variable.
Note: probably there should be a way to lock updating requests as well. For
now "proxy_cache_use_stale updating" is available.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 26 Dec 2011 11:15:23 +0000 |
parents | eae4a59ae59a |
children | d620f497c50f |
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/* * Copyright (C) Igor Sysoev */ #ifndef _NGX_TIMES_H_INCLUDED_ #define _NGX_TIMES_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> typedef struct { time_t sec; ngx_uint_t msec; ngx_int_t gmtoff; } ngx_time_t; void ngx_time_init(void); void ngx_time_update(void); void ngx_time_sigsafe_update(void); u_char *ngx_http_time(u_char *buf, time_t t); u_char *ngx_http_cookie_time(u_char *buf, time_t t); void ngx_gmtime(time_t t, ngx_tm_t *tp); time_t ngx_next_time(time_t when); #define ngx_next_time_n "mktime()" extern volatile ngx_time_t *ngx_cached_time; #define ngx_time() ngx_cached_time->sec #define ngx_timeofday() (ngx_time_t *) ngx_cached_time extern volatile ngx_str_t ngx_cached_err_log_time; extern volatile ngx_str_t ngx_cached_http_time; extern volatile ngx_str_t ngx_cached_http_log_time; extern volatile ngx_str_t ngx_cached_http_log_iso8601; /* * milliseconds elapsed since epoch and truncated to ngx_msec_t, * used in event timers */ extern volatile ngx_msec_t ngx_current_msec; #endif /* _NGX_TIMES_H_INCLUDED_ */