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Re: Intel CPU performance-loss by security-patch?!?

Posted: Wed Jan 03, 2018 6:32 pm
by zullil
Probably just a coincidence. :roll:

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 12:35 am
by zullil

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 2:54 pm
by Joost Buijs
I just installed Windows update KB4056892 which contains a fix for the 'Meltdown vulnerability', the good news is that I don't see any difference in raw calculation speed with my engine at all. My engine runs multithreaded in a single process on a i7-6950X, it is possible that IO is affected and that the fix has some impact on probing the TB's but that is something I still have to check.

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 4:18 pm
by kasinp
Joost Buijs wrote:I just installed Windows update KB4056892 which contains a fix for the 'Meltdown vulnerability', the good news is that I don't see any difference in raw calculation speed with my engine at all. My engine runs multithreaded in a single process on a i7-6950X, it is possible that IO is affected and that the fix has some impact on probing the TB's but that is something I still have to check.
That sounds encouraging, thanks for reporting it.
Peter

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 4:21 pm
by Milos
Joost Buijs wrote:I just installed Windows update KB4056892 which contains a fix for the 'Meltdown vulnerability', the good news is that I don't see any difference in raw calculation speed with my engine at all. My engine runs multithreaded in a single process on a i7-6950X, it is possible that IO is affected and that the fix has some impact on probing the TB's but that is something I still have to check.
You could probably see slowdown in some extent if you are using large pages and big amount of hash.
Slowdown due to TB access will be significant (10-50%) but still much smaller than the difference between TBs on SSD vs HDD. It would be in a ballpark of fast SSD versus regular SSD. So unless you run tests with only specific TB positions you are unlikely to see really visible slowdown.

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 5:03 pm
by schack
Any further observations by anyone who has applied this patch would be most appreciated.

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 5:33 pm
by Michel
Not sure the relevant papers have been mentioned in this thread

https://meltdownattack.com/

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 6:30 pm
by gbtami

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 6:51 pm
by MikeB
zullil wrote:
Probably just a coincidence. :roll:
it was only $39 million - sold all the shares he was allowed to sell (Intel requires CEO to maintain 250,000 shares

This article was written before the latest debacle was publicly known and even then it was suspicious.
Motleyfool
But the avg prices he sold out is only $.30 higher than today's price. The price ran up right after he sold it. For these guys $.30 on 250,000 shares is chump change.

Re: Intel CPU performance-loss by security-patch?!?

Posted: Thu Jan 04, 2018 7:19 pm
by Milos
MikeB wrote:But the avg prices he sold out is only $.30 higher than today's price. The price ran up right after he sold it. For these guys $.30 on 250,000 shares is chump change.
Intel is 4% down today only (while DOW is 0.6% up) and that's just the beginning. So I'd say you are greatly downplaying it.
In the same time AMD up over 5% just today ;).