HZ in RELENG_5? tcp_subr.c related

[Robert Watson]

On Tue, 22 Feb 2005, Kevin Oberman wrote:

> > In RELENG_5, the default HZ for amd64 is 1000, but for all other platforms
> > it is 100.  So amd64 users will see a ten-fold decrease in tcp_isn_tick()
> > running, but i386 (and other) users will see no change.
> 
> Now that 5 is STABLE, I guess we are stuck with it, but in an era of
> "slow" 2GHz systems, it seems like a questionable choice. I know that
> there are a lot of folks running old hardware (like my trusty old K6),
> but they are a minority and changing HZ is not a big deal. Why make the
> majority live with 100 on fast systems or know enough to manually change
> it? 
> 
> Has there been discussion of changing this for V6 or is there a reason I
> missed for keeping HZ at 100 in the iX86 platforms.

In 6-CURRENT, HZ is 1000 for amd64, i386, and ia64, but 100 for other
platforms (i.e., ppc, arm, and alpha).  I'm not opposed to merging the HZ
change to RELENG_5 at some point, but given that occasional nits, such as
the TCP nit, are turning up, I think it's worth waiting until after 5.4.

Robert N M Watson