Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : Load average different for identical servers/requests

[123finder.com]

I have a haproxy load balancer, pushing to 2 servers, same weight, same type of requests. Both server specs are pretty much the same (E3-1230, 8G RAM) and yet one reports a higher loadavg, the other stays near zero. I'm suspecting some config/software setting differences but really don't know what to look for.

What could explain this behavior? Thanks

[storminternet]

Hi,

Are those Linux or Windows servers ?

If its Linux servers then you can use top command to check exactly which processes are executing on server and how much resources like CPU, RAM etc. they are consuming.

On a Windows server, you can use TaskManager ot ProcMon to monitor the processes and their resource usage.

[znetindia]

Hi,

If you are running with linux server, then please update the result of these commands :-
netstat -an | grep :80 | sort -n
netstat -n -p|grep SYN_REC | wc -l

Or if you are on windows, then please run this command and give me that result.
netstat -ano |find /i /c ":80"

[brianoz]

I'd want to compare open connection count, and running processes. Start there. That's probably not going to produce results, but it's the first thing to eliminate.

The next step is to compare memory based settings - do the two have the same memory? Is it all working? What about swap? Memory utilization?

Mysql settings - are they the same? Is the memory cache size the same and working the same way on both servers? Are you using InnoDB on one and MyISAM on the other, or are they both the same?

Is Apache/PHP compiled the same way on both? Or is one DSO and the other CGI? (DSO can be much faster but can be insecure if not set up properly)

Failing that, get someone to look at it for you.

Can you let us know how you go with it and what you find?

[whrss]

Further to what @storminternet said, do check the Input/output wait time and see if there is any latency there.

Also test the physical RAM and compare the disk RPM.

[brianoz]

Originally Posted by whrss

FAlso test the physical RAM and compare the disk RPM.

The type of disk controller may make a difference too - whether it's RAID, and what sort of RAID.