Re: comparison of the AF_ALG interface with the /dev/crypto

[Herbert Xu]

On Thu, Sep 01, 2011 at 04:56:56PM +0200, Nikos Mavrogiannopoulos wrote:
> On Thu, Sep 1, 2011 at 4:14 PM, Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxxx> wrote:
> 
> > Are you maxing out your submission CPU? If not then you're testing
> > the latency of the interface, as opposed to the throughput.
> 
> I think it is obvious that a benchmark of throughput measures
> throughput. If however, you think that AF_ALG is in disadvantage in
> this benchmark, because it is a high latency interface, you're free to
> propose and perform another one. I haven't seen anywhere how is this
> interface was supposed to be used, nor about its qualities (high
> latency, maybe(?) high throughput or so). Thus, I designed this
> benchmark with a use-case in mind, i.e., a TLS or DTLS tunnel
> executing in a system with such an accelerator. There might be other
> benchmarks with other use cases in mind, but I haven't seen any.

Putting TLS data-path in user-space is always going to be less
than optimal, especially with hardware crypto offload, since you'll
be crossing the user-space/kernel boundary multiple times.

The data-path should reside in the kernel so as to avoid that.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/