Opened 3 years ago

Last modified 3 years ago

#2286 closed defect

When I use the proxy_cache_background_update and proxy_cache_use_stale parameter, the expired cache content cannot be returned quickly. — at Version 1

Reported by: magicgaro@… Owned by:
Priority: minor Milestone:
Component: nginx-core Version: 1.19.x
Keywords: background update Cc: magicgaro@…
uname -a: Linux localhost.localdomain 3.10.0-693.el7.x86_64 #1 SMP Tue Aug 22 21:09:27 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
nginx -V: nginx version: nginx/1.19.9
built by gcc 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC)
built with OpenSSL 1.1.1l 24 Aug 2021
TLS SNI support enabled
configure arguments: --prefix=/usr/local/nginx --with-debug --with-cc-opt='-DNGX_LUA_USE_ASSERT -DNGX_LUA_ABORT_AT_PANIC -O2' --add-module=../ngx_devel_kit-0.3.1 --add-module=../echo-nginx-module-0.62 --add-module=../xss-nginx-module-0.06 --add-module=../ngx_coolkit-0.2 --add-module=../set-misc-nginx-module-0.32 --add-module=../form-input-nginx-module-0.12 --add-module=../encrypted-session-nginx-module-0.08 --add-module=../srcache-nginx-module-0.32 --add-module=../ngx_lua-0.10.20 --add-module=../ngx_lua_upstream-0.07 --add-module=../headers-more-nginx-module-0.33 --add-module=../array-var-nginx-module-0.05 --add-module=../memc-nginx-module-0.19 --add-module=../redis2-nginx-module-0.15 --add-module=../redis-nginx-module-0.3.7 --add-module=../rds-json-nginx-module-0.15 --add-module=../rds-csv-nginx-module-0.09 --add-module=../ngx_stream_lua-0.0.10 --with-ld-opt=-Wl,-rpath,/usr/local/nginx/luajit/lib --with-http_stub_status_module --with-http_ssl_module --with-http_realip_module --with-http_geoip_module --with-threads --with-http_v2_module --with-http_stub_status_module --with-http_sub_module --with-threads

Description (last modified by magicgaro@…)

When I use the proxy_cache_background_update on; proxy_cache_use_stale timeout updating;parameter, the expired cache content can't be returned quickly.It seems to be delayed by 200 milliseconds.The following is the process.

backend server i use sleep 5 second.

1.cache miss response time 5s.
# time curl -i -H "Host:test.lua" "127.0.0.1"
HTTP/1.1 200 OK
Cache: MISS
real    0m5.085s

2. cache hit response time 0.004s
# time curl -i -H "Host:test.lua" "127.0.0.1"
HTTP/1.1 200 OK
Cache: HIT
real    0m0.004s

3.cache stale response time 0.205s. (This is obviously unreasonable.)
# time curl -i -H "Host:test.lua" "127.0.0.1"
HTTP/1.1 200 OK
Cache: STALE
real    0m0.205s

4.cache updating response time 0.04s
# time curl -i -H "Host:test.lua" "127.0.0.1"
HTTP/1.1 200 OK
Cache: UPDATING
real    0m0.004s

Is this a bug or is it designed like this?

Change History (1)

comment:1 by magicgaro@…, 3 years ago

Description: modified (diff)
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