Mercurial > hg > nginx-quic
view src/core/ngx_times.h @ 4207:4fc91bae6f83
Better recheck of dead upstream servers.
Previously nginx used to mark backend again as live as soon as fail_timeout
passes (10s by default) since last failure. On the other hand, detecting
dead backend takes up to 60s (proxy_connect_timeout) in typical situation
"backend is down and doesn't respond to any packets". This resulted in
suboptimal behaviour in the above situation (up to 23% of requests were
directed to dead backend with default settings).
More detailed description of the problem may be found here (in Russian):
http://mailman.nginx.org/pipermail/nginx-ru/2011-August/042172.html
Fix is to only allow one request after fail_timeout passes, and
mark backend as "live" only if this request succeeds.
Note that with new code backend will not be marked "live" unless "check"
request is completed, and this may take a while in some specific workloads
(e.g. streaming). This is believed to be acceptable.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 12 Oct 2011 14:22:48 +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_ */