[tor-relays] big spike in cpu usage

[Andreas Krey]

On Sun, 07 Apr 2013 19:42:25 +0000, Moritz Bartl wrote:
...
> 1000 MB (per second!) is not a useful setting.

No, its not 'per second'. It is the amount of allowed traffic that can
be saved up while not hitting the BandwidthRate to be used up when the
BandwidthRate is exceeded. Using up that savings may happen must faster
or much slower than a second depending on settings and use; and it's
doesn't make sense to label the Burst in 'per seconds' just like it
doesn't make sense to label your credit limit in 'dollars per month'.

In my case, I only care that my average bandwith usage doesn't exceed,
say, 1 TB/month; the resulting BandwithRate is 385 KB/s. But I don't
mind it transferring much more as long as this is compensated by earlier
unused BandwithRate. So I don't see a reason why I shouldn't set the
Burst to 1 GB or even 100 GB. (As long as the authorities don't take
the higher traffic as a hint to advertise my relay with more than the
set BandwithRate.)

> (Relay)BandwidthBurst
> should ideally reflect the maximum actual line speed.

That is only useful when you want to save up some bandwith
on a DSL link for your own use; then a big burst would
clog you line. (And I guess Burst=0 would be the proper
thing in that case, unless the implementation is weird
about that.)

Andreas

-- 
"Totally trivial. Famous last words."
From: Linus Torvalds <torvalds@*.org>
Date: Fri, 22 Jan 2010 07:29:21 -0800