Linux bind / dhcp iowait status

Tom Greaser tgreaser at
Wed Mar 15 19:37:46 UTC 2006

also too..
sorry i dont have the sar data avaliable 
to go that far back from where i had the 
phones also running dhcp leases every 4 hours..

but im thinking that didnt seem to make to much of a diff..

im going to break the mirror tonight and
see if is a hardware issue..

Thanks again for the echos..

>>>dhcp at 03/15/06 12:06 pm >>> 
Tom Greaser wrote: 
>have a beefy box that shows 18.40 % iowait at PEAK times 
>and as low as 5.50 % during work hours.. 
>have 2000 phones lease set to 1 day 
>2000 pc lease set to 4 hours.. 
>running ddns on this host ... 
>just wanting to see if this is "normal" 
>will track down to see if its named or dhcpd doing the bulk of IO
>Its an Redhat AS 4 update 3 box with mirrored scsi Ultra 320 drives 
>10000 rpm 
>from free -h 
>buffer 137meg       cache 1627 meg 
That sounds exceedingly high IF the box is only doing DHCP and DNS. 
In fact I'd consider 5.5% to be exceedingly high for such a box. 
What else is running on the box ? 
Does it make any difference if you increase lease times as Glenn
suggests ? 

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