[squid-users] access from same ID and different IP addresses.

[Amos Jeffries]

On 16/03/2016 5:06 p.m., asakura at ioc.dnp.co.jp wrote:
> Hello,
> 
> Recently, in our environment, CPU load on the squid proxy server
> is happening trouble to become a 100%.
> 
> example----
> PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
> 29767 squid     20   0 1430m 1.3g 5332 R 99.1 17.4   6836:56 squid
> 16856 squid     20   0 29764 3280 1620 S  2.0  0.0  68:46.34 squid_kerb_auth
> 16860 squid     20   0 29760 3272 1616 S  1.7  0.0  43:53.67 squid_kerb_auth
> 16855 squid     20   0 22636 1244 1000 S  0.3  0.0   2:57.66 negotiate_wrapp
> 21437 asakura   20   0 15432 1632  932 R  0.3  0.0   0:01.02 top
> 26167 root      20   0 19088 2248 1060 S  0.3  0.0   1016:14 syslog-ng
> ---
> 
> As a result of investigation, We suspect that CPU load become a 100%
> when user attempts to log in from more than different ip addresses. 
> 

All that CPU has to be spent doing something. So what is that something?


> This time, squid has been accessed from 20 or more units of
> the PC with the same user ID.
> When we disable user authentication from target segment, CPU load be low.
> 
> We want to know whether CPU load goes up when squid is accessed from
> a large number of different IP addresses with the same user ID.
> 
> Our environment is below,
> - squid-3.5.1 with squid_kerb_auth(sorry old version...) x5 server

First step is upgrading. So you can see if it is one of the thousand or
so bugs already fixed since that old version.

There have been at least 2 bugs whose claimed symptom was "100% CPU
usage" that got fixed this past year.


Amos