HyperThreading on Intel Xeon Haswell, a benefit?

[Jia-Shiun Li]

On Mon, Dec 15, 2014 at 1:40 PM, grarpamp <grarpamp at gmail.com> wrote:
> Thus to see what people were seeing perf wise.

HTT good for *some* workload? Definitely yes.
HTT good for yours? It depends.
It is not a solution to boost everything.

You really need your own evaluation methods for your own real world workload.
See if this extreme case motivates you.

Script started on Fri Dec 19 04:11:36 2014
root@:~ # uname -a
FreeBSD  11.0-CURRENT FreeBSD 11.0-CURRENT #0 r275582: Sun Dec  7
22:29:51 UTC 2014
root at grind.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64
root@:~ # sysctl hw.model
hw.model: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
root@:~ # sysctl dev.cpu.0.freq
dev.cpu.0.freq: 3600
root@:~ # openssl speed -evp aes-256-cbc
(...)
type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
aes-256-cbc     542270.57k   570008.23k   577700.69k   579443.71k   578661.43k
root@:~ # openssl speed -evp aes-256-cbc -multi 4
(...)
evp            2168111.69k  2283320.41k  2309259.69k  2314799.72k  2323428.69k
root@:~ # openssl speed -evp aes-256-cbc -multi 8
(...)
evp            3720872.65k  4373485.85k  4564089.08k  4615834.28k  4621740.71k
root@:~ # openssl speed -evp aes-256-gcm
(...)
type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
aes-256-gcm     372850.59k   941017.15k  1402284.69k  1518668.74k  1552422.23k
root@:~ # openssl speed -evp aes-256-gcm -multi 4
(...)
evp            1492887.94k  3132772.74k  4501002.29k  4929483.52k  5101510.17k
root@:~ # openssl speed -evp aes-256-gcm -multi 8
(...)
evp            1924978.05k  4533256.96k  6764018.70k  7538217.64k  7985778.30k
root@:~ # openssl speed -evp aes-256-ctr
(...)
type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
aes-256-ctr     491349.11k  1550444.11k  2372213.47k  2755245.59k  2879939.33k
root@:~ # openssl speed -evp aes-256-ctr -multi 4
(...)
evp            1871084.37k  4992105.40k  7707692.29k 10242874.37k 10744955.05k
root@:~ # openssl speed -evp aes-256-ctr -multi 8
(...)
evp            2678304.52k  7575305.94k 11861913.17k 12971657.56k 13356457.98k
root@:~ # ^D  exit

Script done on Fri Dec 19 04:16:08 2014



-Jia-Shiun.