Re: interrupt counts

Mikael Abrahamsson (mike@uplift.sparta.lu.se)
Mon, 19 Aug 1996 10:23:51 +0200 (MET DST)


On Mon, 19 Aug 1996, Matti E Aarnio wrote:

> [ about counter wrapping ]
> > Yes, the same way IP-accounting wrapps pretty quickly as well. 4 gigs over
> > a net isnt a lot today. Is this perhaps something that should be
> > considered for 2.1, to convert more and more of these
> > on-busy-machines-will-wrap-within-a-year counters into 64bit ones? I mean,
> > as speed of machines goes up all the time, wouldnt it be nice to be ahead
> > for a while?
>
> It sure would be nice -- wrap within a year ?

My notion was that the whole kernel should be looked over for these
quickly-wrappable pointers, and they should be converted. The only one
that I personally have noticed is this IP-accounting thing. I tend to see
more and more of these as times passes by though, since
memory/speed/diskspace increases at an enormous pace.

> Hmm.. ftp.funet.fi: Uptime now 32 days, FDDI interface output
> packets count is 1.2 billion, average FTP payload dataflow per
> day is 20-24 GB (weekends are around 15-17 GB per day).
> TCP overheads, WWW, and several other services not counted.

Yes, ftp.funet.fi was in my thoughts as well. ftp.cdrom.com the same
way... :)

> HOWEVER, I might want to have it as a configuration option.
> At low-level 386/25 (my home machine) I am entirely happy
> with 32-bit counters.
>
> bool 'Do you want unwrappable (64 bit) network counters ?' \
> CONFIG_LONG_NETWORK_COUNTERS

I dont know how much handling 64bit instead of 32 bit decereases
performance, but this is definately an option.