Fast random generator was: Re: Ideas for v2.1

Uwe Bonnes (
Tue, 2 Jul 1996 14:26:55 +0200


as I have problems with bad blocks on a harddisk, I find it usefull to write
random data to the disk to probe that. However the speed of /dev/urandom
doesn't match the write speed of modern harddisks at all:
elektron:/mnt1/home> time dd if=/dev/urandom of=/dev/null bs=1k count=1k
1024+0 records in
1024+0 records out
0.000u 4.040s 0:04.08 99.0% 0+0k 0+0io 42pf+0w
That's about 250 kByte/sec. This is with a Pentium 100

So I would like to see a fast (possibly much mor predictable) random
generator device (/dev/fandom), running with perhaps 5 MBytes/sec or better
above. Is that feasable?

Uwe Bonnes      

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