HZ in RELENG_5? tcp_subr.c related
rwatson at FreeBSD.org
Tue Feb 22 19:57:45 GMT 2005
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
> 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
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