
Memory Barriers: A Hardware View for Software Hackers (2010) [pdf] - Tomte
http://www.rdrop.com/users/paulmck/scalability/paper/whymb.2010.07.23a.pdf
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dewyatt
This is a lot of interesting information. I hope that one day we can avoid
this level of complexity though. We have enough to worry about with modern
computer systems.

I wrote a driver for FreeBSD recently and had to implement memory barriers to
get it accepted into mainline. I had never dealt with memory barriers before
and I couldn't help but think "great! what is this new thing I have to keep in
mind?" It wasn't all that difficult, but still...

We have built up so many layers of complexity that it's becoming very
difficult to secure things, for example. I really hope we can somehow
drastically simplify computers/software in the future.

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dman
Only if we stop worshipping at the altar of speed. We are collectively so
obsessed about maximizing speed related metrics that simplicity often takes a
backseat.

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vvanders
Speed = battery life which I for one find somewhat important.

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dman
Agree with you on that front. In fact on my laptop i would happily trade some
latency/responsiveness to get battery life. ie let the os batch some wireless
/ IO / computation together and do it at one go when it wakes up relevant
hardware from its sleep state.

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vvanders
Modern hardware is actually really good at DCVS. You don't trade latency for
battery life, just doing less work gets you better battery efficiency.

There's a really gnarly V*I curve which is not linear(as clock speed
increases, voltage also needs to come up) which makes good performance even
more key.

