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| author | Maxim Dounin <mdounin@mdounin.ru> | 2011-12-26 11:15:23 +0000 |
|---|---|---|
| committer | Maxim Dounin <mdounin@mdounin.ru> | 2011-12-26 11:15:23 +0000 |
| commit | 822fe46934435956b710c781aa0dde7e5044e929 (patch) | |
| tree | 23d6bea9fd32e4d63480487fc9fd12823d7bf343 /src/http/modules/ngx_http_proxy_module.c | |
| parent | 0c88994a0370af04ed1d9dc09f16e695bfd0a343 (diff) | |
| download | nginx-822fe46934435956b710c781aa0dde7e5044e929.tar.gz nginx-822fe46934435956b710c781aa0dde7e5044e929.tar.bz2 | |
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.
Diffstat (limited to 'src/http/modules/ngx_http_proxy_module.c')
| -rw-r--r-- | src/http/modules/ngx_http_proxy_module.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c index a525cd922..b65093b72 100644 --- a/src/http/modules/ngx_http_proxy_module.c +++ b/src/http/modules/ngx_http_proxy_module.c @@ -402,6 +402,20 @@ static ngx_command_t ngx_http_proxy_commands[] = { offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_methods), &ngx_http_upstream_cache_method_mask }, + { ngx_string("proxy_cache_lock"), + NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG, + ngx_conf_set_flag_slot, + NGX_HTTP_LOC_CONF_OFFSET, + offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_lock), + NULL }, + + { ngx_string("proxy_cache_lock_timeout"), + NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, + ngx_conf_set_msec_slot, + NGX_HTTP_LOC_CONF_OFFSET, + offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_lock_timeout), + NULL }, + #endif { ngx_string("proxy_temp_path"), @@ -2435,6 +2449,8 @@ ngx_http_proxy_create_loc_conf(ngx_conf_t *cf) conf->upstream.cache_bypass = NGX_CONF_UNSET_PTR; conf->upstream.no_cache = NGX_CONF_UNSET_PTR; conf->upstream.cache_valid = NGX_CONF_UNSET_PTR; + conf->upstream.cache_lock = NGX_CONF_UNSET; + conf->upstream.cache_lock_timeout = NGX_CONF_UNSET_MSEC; #endif conf->upstream.hide_headers = NGX_CONF_UNSET_PTR; @@ -2681,6 +2697,12 @@ ngx_http_proxy_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) conf->cache_key = prev->cache_key; } + ngx_conf_merge_value(conf->upstream.cache_lock, + prev->upstream.cache_lock, 0); + + ngx_conf_merge_msec_value(conf->upstream.cache_lock_timeout, + prev->upstream.cache_lock_timeout, 5000); + #endif if (conf->method.len == 0) { |