[OpenAFS] low write/read performance with 1.8.x 1.9.0 client

[Giovanni Bracco]

Yes, of course, I really meant that the way OpenAFS client provides 
encryption is really "spectacularly bad", as you wrote!

Giovanni

On 13/10/20 21:33, Benjamin Kaduk wrote:
> On Tue, Oct 13, 2020 at 09:26:43PM +0200, Giovanni Bracco wrote:
>> Sorry for the typing mistake in  previous mail, but you got the point!
>>
>> Now with the proper setting at the client startup the result is clear,
>> the low performance was indeed due to encryption on!
>>
>> Thank you, the case is solved but it is indeed impressive that
>> encrypting the data transfer reduces performances of a factor 5 !
> 
> I don't think you should draw a generic conclusion about encrypting data in
> general -- the fcrypt algorithm used by rxkad is spectacularly bad.  It is
> based off DES, which in turn was specifically designed to be slow to
> implement in software, and does not make use of modern processor features
> like AESNI.  My testing during rxgk development was easily able to encrypt
> traffic fast enough to saturate a gigabit link, on commodity hardware, with
> an AES-based cipher.
> 
> -Ben
> 

-- 
Giovanni Bracco
phone  +39 351 8804788
E-mail  giovanni.bracco@enea.it
WWW http://www.afs.enea.it/bracco