Hello,
I am using haproxy-1.5.14 and sometimes I see the following errors in the log:
Oct 7 08:33:03 srv1 haproxy[77565]: unix:1 [07/Oct/2015:08:33:02.428] MT-front
MT_RU_EN-back/<NOSRV> 0/1000/-1/-1/1000 503 212 - - sQ-- 125/124/108/0/0 0/28
"POST /some/url HTTP/1.1"
(many similar at one moment)
Common part in these errors is "1000" in Tw and Tt, and "sQ--" termination
state.
Here is the relevant part on my config (I can post more if needed):
defaults
balance roundrobin
maxconn 10000
timeout queue 1s
fullconn 3000
default-server inter 5s downinter 1s fastinter 500ms fall 3 rise 1
slowstart 60s maxqueue 1 minconn 5 maxconn 150
backend MT_RU_EN-back
mode http
timeout server 30s
server mt1-34 mt1-34:19016 track MT-back/mt1-34 weight 38
server mt1-35 mt1-35:19016 track MT-back/mt1-35 weight 38
<total 18 of similar servers>
So this error log indicates that request was sitting in the queue for timeout
queue==1s and his turn did not come.
In the stats web interface for MT_RU_EN-back backend I see the following
numbers:
Sessions: limit=3000, max=126 (for the whole backend)
Limit=150, max=5 or 6 (for each server)
If I understand minconn/maxconn meaning right, each server should accept up to
min(150, 3000/18) connections
So according to stats the load were far from limits.
What can be the cause of such errors?
Thanks!
