Hi Eric,
On 12/21/2020 3:20 PM, Eric Biggers wrote:
On Fri, Dec 18, 2020 at 01:10:57PM -0800, Megha Dey wrote:
Optimize crypto algorithms using VPCLMULQDQ and VAES AVX512 instructions
(first implemented on Intel's Icelake client and Xeon CPUs).
These algorithms take advantage of the AVX512 registers to keep the CPU
busy and increase memory bandwidth utilization. They provide substantial
(2-10x) improvements over existing crypto algorithms when update data size
is greater than 128 bytes and do not have any significant impact when used
on small amounts of data.
However, these algorithms may also incur a frequency penalty and cause
collateral damage to other workloads running on the same core(co-scheduled
threads). These frequency drops are also known as bin drops where 1 bin
drop is around 100MHz. With the SpecCPU and ffmpeg benchmark, a 0-1 bin
drop(0-100MHz) is observed on Icelake desktop and 0-2 bin drops (0-200Mhz)
are observed on the Icelake server.
Do these new algorithms all pass the self-tests, including the fuzz tests that
are enabled when CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y?
I had tested these algorithms with CRYPTO_MANAGER_DISABLE_TESTS=n and
tcrypt, not with
CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y (I wasn't aware this existed, my bad).
I see a couple of errors after enabling it and am working on fixing those.
Megha
- Eric
