Re: [resent PATCH] Re: very slow parallel read performance

Alex Bligh - linux-kernel
2001-08-27T22:26:56Z

--On Monday, 27 August, 2001 11:38 PM +0200
Oliver.Neukum@lrz.uni-muenchen.de wrote:

> How do you measure cost of
> replacement ?

See previous mail with cost of E. However, this
is broken w.r.t. differential speed of consumption
by tasks, and as Daniel points out, if the system
works as he's designed/designing, the key will be
sizing readahead sufficiently intelligently that
drops happen infrequently anyway. If it works like
TCP windows, it need not be particularly intelligent
(very punitive, but infrequent), and we can do
the tweaks of what packets to drop (cf RED in TCP)
later.

My point w.r.t. penalizing fast consumers is that
negative feedback in a control system isn't necessarily
bad.

--
Alex Bligh