Re:Google says Rowhammer attacks are gaining range as RAM is...
by njibhu on Saturday May 29, 2021 @06:42AM
(#27324339)
This article from Crucial probably explains the two arguments:
https://www.crucial.com/articles/about-memory/difference-bet...
But their conclusion is that practical latency has indeed decreased over the last 15 years.
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Re:Google says Rowhammer attacks are gaining range as RAM is...
by beebeepka on Saturday May 29, 2021 @08:48AM
(#27324910)
After looking at the table, I am ready to swallow my pride. Looks like practical latencies have changed a tiny bit. So me and the person I replied to originally were both wrong
Re:Google says Rowhammer attacks are gaining range as RAM is...
by formerly_proven on Saturday May 29, 2021 @12:41PM
(#27326415)
You were wrong about the memory latency¹ increasing, but the memory latency² has increased (substantially) for most systems, while the memory latency³ has indeed decreased. In general, the memory latency¹ has not improved much. Of course, the memory latency⁴ has greatly increased, due to the clock frequency being increased so much to enable the higher bandwidth, while the memory latency¹ stayed mostly the same.
[1] as in: access latency of the DRAM [2] as in: how long does a CPU memory read which is _not_ cached take [3] as in: how long does a CPU memory read on average take [4] as in: CL
Re:Google says Rowhammer attacks are gaining range as RAM is...
by namibj on Saturday May 29, 2021 @10:14AM
(#27325367)
Also note that practical non-high-capacity DDR4 setups reach 3600 CL16.
That's way faster than the 3200 CL22 they gave at the bottom.
Re:Google says Rowhammer attacks are gaining range as RAM is...
by staticassertion on Saturday May 29, 2021 @04:05PM
(#27327883)
No, I was right. Not that it matters, feel free to replace latency with bandwidth. Or replace it with nothing and focus on capacity. It's a blip on my point, which is that the architecture has changed considerably to allow for progress in other areas.