Initial 6.1 questions

Robert Watson rwatson at
Mon Jun 12 20:08:14 UTC 2006

On Mon, 12 Jun 2006, Scott Long wrote:

> I run a number of high-load production systems that do a lot of network and 
> filesystem activity, all with HZ set to 100.  It has also been shown in the 
> past that certain things in the network area where not fixed to deal with a 
> high HZ value, so it's possible that it's even more stable/reliable with an 
> HZ value of 100.
> My personal opinion is that HZ should gop back down to 100 in 7-CURRENT 
> immediately, and only be incremented back up when/if it's proven to be the 
> right thing to do. And, I say that as someone who (errantly) pushed for the 
> increase to 1000 several years ago.

I think it's probably a good idea to do it sooner rather than later.  It may 
slightly negatively impact some services that rely on frequent timers to do 
things like retransmit timing and the like.  But I haven't done any 

Robert N M Watson
Computer Laboratory
Universty of Cambridge

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