Andrey Repin wrote:
> I was need to pipe some bytes through application and watch it's reaction.
> But with /dev/urandom the stream speed is only about 40Mb/sec. Using
> /dev/zero, however, makes it 3 orders of magnitude faster (~35Gb/s), but for
> technical reasons, using monotonous sequence is highly undesirable. Is there
> any more performant source of non-monotonous byte sequences available to
> Cygwin? I would be pretty happy even with sequential bytes, I think. Only two
> reservations are good performance (something around 100 Mb/sec or more would
> suffice) and a degree of randomness.
You want a source of data that's non-monotonous but faster than /dev/urandom.
I don't see how this is a Cygwin issue at all, and thus I don't think it
belongs on this list.
Nonetheless, I suspect the easiest solution is to write a short C program to
produce your output, along the lines of (untested):
#include <stdio.h>
int main () {
unsigned char c;
for (c = 0;; c++)
putchar(c);
}
Alternatively, pre-cache some output and use that:
head --bytes=1G >/var/cache/randomdata
./myapp <(while :;do cat /var/cache/randomdata; done)
--
Adam Dinwoodie
Messages posted to this list are made in a personal capacity.
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