nicolasff/phpredis — Issue #80: Check Apache status
Author: nicolasff
Created: 2011-11-14 22:56:34+00:00
State: open

what we noticed is that on apache server-status we had lots of open connections here is example "screenshot",
except at that time we had 1000 "W" connections - this was same on all three servers.

Current Time: Monday, 14-Nov-2011 21:24:45 UTC
Restart Time: Monday, 14-Nov-2011 10:05:48 UTC
Parent Server Generation: 0
Server uptime: 11 hours 18 minutes 57 seconds
Total accesses: 961709 - Total Traffic: 127.8 MB
CPU Usage: u485.38 s170.63 cu0 cs0 - 1.61% CPU load
23.6 requests/sec - 3290 B/second - 139 B/request
207 requests currently being processed, 125 idle workers
WW_W_WW__W_WW__W_.WW_WW_WWWW_CW_CWW___WWWWWWWWWWW_W_W_WWW__CWWWW
WW_.____WWWWW__WW__WWC_WW_WWWW___W___W__W_WW_W_W_WWWW__WWW__WW_W
_____WWC_W___WW.WWW__WW____W___W.WWW__W___WW.__W__WW.WW_W...WWWW
WW_WW_.__..W.W._.W_WWWW__WWW.._W__WW_C.W_WW_W.._.WWW.W_CWWWW._CW
W__WWWWW._WW__..WW.W_W_W_W.W__W._.W._._WW__W._...C.W._W_WW.W.WWW
...WCWWW_WW.W.W._WWWWW_W_WW__......W_.._W..WW..W_.W..W......W...
WW.W_.W....W.W...W..W....W...._....W........_.W......W__........
.........W......................................................
................................................................
................................................................
................................................................

this all is "normal" but we noticed that if we stop nginx, connections still remains, until we HUP the apache server.
for one of the servers we did investigate some more and we found out that the apache server process (which includes PHP)
have open connection to the redis server.
there were no open connections to the nginx (which at that time was stopped anyway).