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@requiem @thegibson If I may be allowed to be pedantic here, I ask that my words be considered with some gravity.

The issue isn't static logic. The issue is divorcing instruction decoding from instruction set design to attain performance goals not originally built into the ISA.

It takes, for example, several clock cycles just to decode x86 instructions into a form that can then be readily executed. Several clocks to load the code cache. Several clocks to translate what's in the code cache into a pre-decoded form in the pre-decode cache. Several clocks to load a pre-decode line into the instruction registers (yes, plural) of the instruction fetch unit. A clock to pass that onto the first of (I think?) three instruction decode stages in the core. Three more clocks after that, you finally have a fully decoded instruction that the remainder of the pipelines (yes, plural) can potentially execute.

Of course, I say potentially because there's register renaming happening, there's delays caused by waiting for available instruction execution units to become available in the first place, there's waiting for result buses to become uncontested, ...

The only reason all this abhorrent latency is obscured is because the CPU literally has hundreds of instructions in flight at any given time. Gone are the days when it was a technical achievement that the Pentium had 2 concurrently running instructions. Today, our CPUs, have literally hundreds.

(Consider: a 7-pipe superscalar processor with 23 pipeline stages, assuming no other micro-architectural features to enhance performance, still offers 23*7=161 in-flight instructions, assuming you have some other means of keeping those pipes filled.)

This is why CPU vendors no longer put cycle counts next to their instructions anymore. Instructions are pre-decoded into short programs, and it's those programs (strings of "micro-ops", hence micro-op caches, et. al.) which are executed by the core on a more primitive level.

Make no mistake: the x86 instruction set architecture we all love to hate today has been shambling undead zombie for decades now. RISC definitely won, which is why every x86-compatible processor has been built on top of RISC cores since the early 00s, if not earlier. Intel just doesn't want everyone to know it because the ISA is such a cash cow these days. Kind of like how the USA is really a nation whose official measurement system is the SI system, but we continue to use imperial units because we have official definitions that maps one to the other.

Oh, but don't think that RISC is immune from this either. It makes my blood boil when people say, "RISC-V|ARM|MIPS|POWER is immune."

No, it's not. Neither is MIPS, neither is ARM, neither is POWER. If your processor has any form of speculative execution and depends on caches for maintaining instruction throughputs, which is to say literally all architectures on the planet since the Pentium-Pro demonstrated its performance advantages over the PowerPC 601, you will be susceptible to SPECTRE. Full stop. That's laws of physics talking, not Intel or IBM.

Whether it's implemented as a sea-of-gates in some off-brand ASIC or if it's an FPGA, or you're using the latest nanometer-scale process node by the most expensive fab house on the planet, it won't matter -- SPECTRE is an artifact of the micro-architecture used by the processor. It has nothing whatsoever to do with the ISA. It has everything to do with performance-at-all-costs, gotta-keep-them-pipes-full mentality that drives all of today's design requirements.

I will put the soapbox back in the closet now. Sorry.

What do Tassie folks think of Kingston High? Ok, Meh or avoid?

Looks like its our area school, Taroona aren't taking out of area enrolments, and we can't afford Friends.

Boost this if you want to be part of an explicitly anticapitalist technology liberation movement.

Oh noes. VLC went all web 3.0 and now is a horrible flat mess of unnavigable rubbish, with no simple way to just drag a bunch of music in and have it just play. I don't even know of an alternative these days, have been using VLC for so long....

Australians should be asking why isn't publishing their government funded content directly into the social cloud by way of ActivityPub protocols.

Currently running debian testing, debian 10 that I had in the MacBook doesn't do a lot of stuff, 5.10 kernel has the required bits!

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New tool, a ThinkPad X1 carbon after my old MacBook air stopped reliably waking. Suitably personalised for a beginning!

What is your choice if you leave #CentOS?

Please help me share.

:redhat: :centos: :clearos: :rockylinux: :fedora:

#FreeSoftware #OpenSource #GNU #Linux

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Another honey harvest today, around 15 kg at the price of six stings. I'm going to feel a bit shite for the next day or two. One more hive to harvest, it needs a few more weeks to be fully capped. Hard work, but good fun!

MH-, Breakup 

Well, our house became a bit of a safe space for my wife's sister, She's less lonely here and was able to focus on getting some things done and have a bit of a chat. Looks to be the marriage is completely over, she's said there's no coming back from it now.

So, I focus on parenting so my wife can support her sister as needed.

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Anyone have a way to contact Craig Miskell at gitlab? Just had a thought about his tyranny of the clock talk, on the spikes at 45 seconds. Possibly to do with sources synchronized to GPS or TAI time vs UTC. Though that appears to be backwards:

MH-, Breakup 

SIL's husband of 10+ years is very ill mentally, undiagnosed but depressed and has seen trauma in war, and wants to end the marriage. I am completely lost on how to help here :(

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