>>
>> for CPU-based alg, we have completed the compr/decompr within
>> crypto_acomp_decompress()
>> synchronously. they won't return EINPROGRESS, EBUSY.
>>
>> The problem is that crypto_acomp won't expose this information to its
>> users. if it does,
>> we can use this info, we will totally avoid the code of copying
>> zsmalloc's data to a tmp
>> buffer for the most majority users of zswap.
>>
>> But I am not sure if we can find a way to convince Herbert(+To) :-)
> What would you like to expose? The async status of the underlying
> algorithm?
Right. followed by a rfc patchset, please help take a look.
>
> We could certainly do that. But I wonder if it might actually be
> better for you to allocate a second sync-only algorithm for such
> cases. I'd like to see some real numbers.
some hardware might want to use an accelerator to help offload CPU's
work. their drivers are working in async mode, for example, hisilicon
and intel.
I don't have the exact number we can save by removing the redundant
memcpy, nor do i have a proper hardware to test and get the number.
As Chengming is actually working in zswap, i wonder if you can test
my patches and post some data?
>
> Cheers,
> --
> Email: Herbert Xu <[email protected]>
Thanks
Barry
On Wed, Jan 03, 2024 at 03:57:59PM +1300, Barry Song wrote:
>
> > We could certainly do that. But I wonder if it might actually be
> > better for you to allocate a second sync-only algorithm for such
> > cases. I'd like to see some real numbers.
>
> some hardware might want to use an accelerator to help offload CPU's
> work. their drivers are working in async mode, for example, hisilicon
> and intel.
>
> I don't have the exact number we can save by removing the redundant
> memcpy, nor do i have a proper hardware to test and get the number.
> As Chengming is actually working in zswap, i wonder if you can test
> my patches and post some data?
I don't have the hardware to test this. Since you're proposing
the change, please test it to ensure that we're not adding cruft
to the API that's actually detrimental to performance.
Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt