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    SubjectRe: [PATCH] (0/4) Entropy accounting fixes
    On Sat, Aug 17, 2002 at 08:08:36PM -0700, Linus Torvalds wrote:
    >
    > On Sat, 17 Aug 2002, Oliver Xymoron wrote:
    > >
    > > Let me clarify that 2-5 orders thing. The kernel trusts about 10 times
    > > as many samples as it should, and overestimates each samples' entropy
    > > by about a factor of 10 (on x86 with TSC) or 1.3 (using 1kHz jiffies).
    >
    > Lookin gat the code, your _new_ code just throws samples away _entirely_
    > just because some random event hasn't happened (the first thing I noticed
    > was the context switch testing, there may be others there that I just
    > didn't react to).

    No, it still mixes them in.

    > In short, you seem to cut those random events to _zero_. And this happens
    > under what seems to be perfectly realistic loads. That's not trying to fix
    > things, that's just breaking them.
    >
    > > The patches will be a nuisance for anyone who's currently using
    > > /dev/random to generate session keys on busy SSL servers.
    >
    > No, it appears to be a nuisanse even for people who have real issues, ie
    > just generating _occasional_ numbers on machines that just don't happen to
    > run much user space programs.

    Read the code again. Better yet, try it.

    23:06ash~$ cat /proc/sys/kernel/random/entropy_avail
    4096
    23:17ash~$ w
    23:17:22 up 11 min, 2 users, load average: 0.09, 0.06, 0.05

    It was probably full in less than 11 minutes.

    --
    "Love the dolphins," she advised him. "Write by W.A.S.T.E.."
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