Re: Default number of overwrites in shred

[Pádraig Brady]

HggdH wrote:
> On Mon, 2009-01-26 at 10:20 +0000, Pádraig Brady wrote:
>> Pádraig Brady wrote:
>>> Thanks for performance testing, showing reading /dev/urandom is the 
>>> bottleneck.
>> It would be worth knowing what CPU you used for this test.
>>
>> cheers,
>> Pádraig.
> 
> An AMD64 Turion, 2 cores @ 2GHz. The disk interface is a SATA UDMA/133. 
> 
> Please keep in mind I have not yet run a real performance test (multiple
> runs, multiple file sizes).

Yes cache may bias the results somewhat, though /dev/urandom is surprisingly 
slow:

$ dd bs=1M count=100 if=/dev/urandom of=/dev/null
100+0 records in
100+0 records out
104857600 bytes (105 MB) copied, 23.3218 seconds, 4.5 MB/s