Re: Off-topic - Apache Config - Load crises

[Jim Cox <ji...@jimco-fwt.com>]

Your problem may be a network problem, not Apache/Mod_perl.

Check with your upstream provider and have them do a bandwidth 
analysis. Here is why.

I've strobed your network and the return time latency seems to be high. 

It would appear that you have about a 28 ms latency overhead in/out of 
your network. That is not a good sign. This is on top of what appears to 
be a standard 1.54 - 2.0 Mbps line.  If your upstream feed is more than
a T1 or E1 then you need to have a talk with your upstream. 

I suggest invest some time in bing. (bing not ping)

Of course I'm looking at this through about 20 hops and because of 
that most of my information is inconclusive. I have noted that
codix-pri-gw.uk.insnet.net, which appears to be an assigned router 
by your upstream, appears to be dropping packets.  I get a 40% packet
loss when I test to that address and beyond.

Anyway, SWAG if this helps, good.  If it did not help,... don't blame me,
I'm not in the UK. 
 

Rafiq Ismail wrote:
> 
> I know this is a bit off topic, but I could use some immediate advise on
> server config?
> 
> Got a server which is getting hit really bad.
> Have to keep it up.  I've got:
> 
> P Timeout 300
> 
> # Keepalive, better on this server...
> KeepAlive               On
> MaxKeepAliveRequests    100
> KeepAliveTimeout        5
> 
> # performance services
> MinSpareServers         5
> MaxSpareServers         50
> StartServers            20
> StartServers            20
> MaxClients              250
> 
> Pings look like:
> 
> 64 bytes from x.x.x.x: icmp_seq=0 ttl=244 time=1069.3 ms
> 64 bytes from x.x.x.x: icmp_seq=1 ttl=244 time=984.8 ms
> 64 bytes from x.x.x.x: icmp_seq=2 ttl=244 time=1138.9 ms
> 64 bytes from x.x.x.x: icmp_seq=3 ttl=244 time=1567.1 ms
> 64 bytes from x.x.x.x: icmp_seq=4 ttl=244 time=1622.3 ms
> 64 bytes from x.x.x.x: icmp_seq=5 ttl=244 time=1382.8 ms
> 64 bytes from x.x.x.x: icmp_seq=6 ttl=244 time=1145.5 ms
> 64 bytes from x.x.x.x: icmp_seq=7 ttl=244 time=1065.6 ms
> 64 bytes from x.x.x.x: icmp_seq=8 ttl=244 time=1133.6 ms
> 
> There are some really graphic intensive pages here, however I'm not sure
> if Keep alive is good when there's lots of contention for pages.  Should
> I:
>          i) disable keep alive?
> 
>         ii) reduce the keep alive time out ?
> 
>        iii) up my number for max spare servers?  Since i've not maxed out
> on load or memory, perhaps more idle servers will reduce the contention
> for apache children?  My intutition is that since the server is obviously
> in trouble, resource wise, perhaps increasing the number of daemons will
> relieve the load.  Not sure.  It's a big box.  Any ideas?
> 
>        iv) Something else?
> 
> I'd appreciate some suggestions.
> 
> Thanks,
> 
> R.
> 
> --
> Rafiq Ismail
> 
> Software Engineer and Systems Administrator
> http://www.codix.net
> 
> "All the best people in life seem to like Linux." - Steve Wozniak

-- 
Jim Cox (mailto:jim@jimco-fwt.com) 
(817) 315-8134           (888) 834-7656 Toll Free
(817) 315-8253 FAX