This is not about reclaiming memory by swapping the contents out to disk. It is about killing processes due to having overcommitted beyond the available memory plus swap space. The processes thrown out of the plane (targeted by the OOM killer) cannot be resurrected
Fair enough. I still think that the analogy is a bit overzealous given that my issue with the hypothetical weight-shedding strategy is ethical rather than technical.
It’s not a cargo cult if the actions directly cause cargo to arrive based on well understood mechanics.
Regardless of whether it would be better in some situations to align to 128 bytes, 64 bytes really is the cache line size on all common x86 cpus and it is a good idea to avoid threads modifying the same cacheline.
It indeed isn't, but I've seen my share of systems where nobody checked if cargo arrived. (The code was checked in without any benchmarks done, and after many years, it was found that the macros used were effectively no-ops :-) )
> even on x86 on recent server CPUs, cache-coherency protocols may be operating at a different granularity than the cache line size. A typical case with new Intel server CPUs is operating at the granularity of 2 consecutive cache lines
I don’t think it is accurate that Intel CPUs use 2 cache lines / 128 bytes as the coherency protocol granule.
Yes, there can be additional destructive interference effects at that granularity, but that’s due to prefetching (of two cachelines with coherency managed independently) rather than having coherency operating on one 128 byte granule
AFAIK 64 bytes is still the correct granule for avoiding false sharing, with two cores modifying two consecutive cachelines having way less destructive interference than two cores modifying one cacheline.
Original iPods (and early iPhones) weren’t locked down as much. There were a number of utils that could manage your library. ml_ipod plugin for WinAmp comes to mind.
This was in the “truth” posted by Trump on his social media announcing the deal:
> It is my Great Honor to report that the United States of America now fully owns and controls 10% of INTEL, a Great American Company that has an even more incredible future. I negotiated this Deal with Lip-Bu Tan, the Highly Respected Chief Executive Officer of the Company. The United States paid nothing for these Shares, and the Shares are now valued at approximately $11 Billion Dollars. This is a great Deal for America and, also, a great Deal for INTEL. Building leading edge Semiconductors and Chips, which is what INTEL does, is fundamental to the future of our Nation. MAKE AMERICA GREAT AGAIN! Thank you for your attention to this matter.
The president has been known to not know all the facts or exaggerate about what is known. Personally, and sadly, his tweets are worthless than my fortune cookies.
There is an important difference between these scenarios:
1) A member of the opposition party tweets "The president stabbed a kid" without any proof. I go on facebook and post "WTF why did the president stab a kid? He is so evil."
2) The president tweets "I just stabbed a kid" without any proof. I go on facebook and post "WTF why did the president stab a kid? He is so evil."
In general its a good rule to avoid using any politician's quote as fact. Especially at the federal level, they've all made a career of exaggerating and telling partial truths to earn media coverage and votes.
Let’s not “both sides” his behavior. This president lies about everything, and actively causes harm by lying maliciously about people he would like his followers to target.
I'm not "both sides"-ing it. Presidents all lie frequently, I'd argue they lie about most things. Without knowing what the truth actually is we would have no way of knowing who lies more, and at the end of the day my concern is with them lying at all rather than to what degree they lie to the public.
There is quite a difference between. exaggeration and blunt lies.
Also most exaggeration happens during campaigns for getting votes, but rarely the result is a strong enough mandate to push all things through, thus one has to compromise ... but campaigning on "well, realistically my options will be limited" doesn't really work, especially as the campaign promises form the negotiation base lateron.
What you point to is an odd reversal for sure. Trump is actually doing many of the things he campaigned on while most candidates lie during the campaign. Trump now lies about seemingly obvious or unimportant things now in office, where many presidents either wouldn't waste a lie on something unimportant or wouldn't bother acknowledging the topic at all.
They all still lie though. Whether a particular lie can be considered an exaggeration boils down to how strict a line one draws around what a lie is. To me, if a president speaks only a partial truth or a misrepresentation if information they very much have access to, its a lie.
He told the truth, but also many lies in parallel. Where is the wall that mexico paid? Where is the peace in Israel and Ukraine? 6 days are over. The truths in between this are useless.
Can you find a president in recent history that didn't fall short of many or most of their campaign promises?
I don't say that to defend trump, the guys is a narcissistic asshole. I only say that to point to the fact that he's doing what any other politician does - say what it takes to get elected then play the game that makes you the most money.
Are you sure congress didn’t authorize this ? i.e. actually specified that the money could only be used for grants and could not be used for equity purchases?
> The Department of Commerce is authorized to provide funding in various forms, including grants, cooperative agreements, loans, and loan guarantees, in exercising its Section 9902 authorities
AFAICT the relevant section of law says it is up to the Secretary of Commerce to determine the funding type to be used for the semiconductor financial assistance
I thought this too, but after reading some of the other comments here I read some of the text of the chips act and the 2021 NDAA (mostly section 9902) and AFAICT Congress appropriated a bunch of money for financial assistance for semiconductor companies and gave the Dept of Commerce the authority to determine the funding type.
That they were grants instead of any other instrument appears to be a Biden Commerce decision, not a congressional one.
I’m no lawyer and could certainly be missing something i the law that says it has to be grants but from what I see it looks like figuring out what to do the the money was pretty much delegated to dept of commerce with limited direction about eligibility and review criteria.
> The NMOS transistors used in the 6502 were quite large and worked on the basis of electrostatic charges ... as opposed to bipolar transistors that are inherently quantum in operation
Forming a conductive channel in silicon in any FET and semiconductivity in general is an inherently quantum effect too, right?
If you go deep enough in the details, everything is a "quantum effect".
However, in order to design and simulate a MOS transistor and most of the other semiconductor devices you do not need to use any quantum physics.
This should be made obvious by the fact that both the metal-semiconductor transistor (i.e. MESFET, patent filed on 1925-10-22) and the depletion-mode metal-insulator-semiconductor transistor (i.e. depletion-mode MOSFET, patent filed on 1928-03-28) have been invented at a time when quantum theory was just nascent, not yet applicable to semiconductors and certainly unknown to the inventor (Julius Edgar Lilienfeld; despite the fact that the FET operating principles were obvious, the know-how for making reproducible semiconductor devices has been acquired only during WWII, as a consequence of the development of diode detectors for radars, which generated the stream of inventions of semiconductor devices after the war ended).
For designing MOSFETs, you just need to use classical electrodynamics, together with several functions that provide the semiconductor material characteristics, like intrinsic free carrier concentration as a function of temperature, carrier mobilities as functions of temperature and impurity concentrations (and electric field at high fields), ionization probabilities for impurities, avalanche ionization coefficients, dielectric constants, and a few others.
It would be nice if instead of measuring experimentally all the characteristic functions for a semiconductor material one could compute them using quantum theory, but that is currently not possible.
So for semiconductor device design, quantum physics is mostly hidden inside empirically determined functions. Only few kinds of devices, e.g. semiconductor lasers, may need the use of some formulas taken from quantum physics, e.g. from quantum statistics, but even for them most of their mathematical model is based on classical physics.
> This should be made obvious by the fact that both the metal-semiconductor transistor (i.e. MESFET, patent filed on 1925-10-22) and the depletion-mode metal-insulator-semiconductor transistor (i.e. depletion-mode MOSFET, patent filed on 1928-03-28) have been invented at a time when quantum theory was just nascent,
I don't think that makes it obvious at all, given that the none of these invented devices actually worked, and the first working MOSFETs weren't until the late 50s after a research program of a few additional decades by a bunch of solid-state physicists at Bell Labs (who did know and develop quantum theories of solids - Shockley, Bardeen, Brattain - not successful in making a FET -Atalla, Kahng, many others)
"Electrons and Holes in Semiconductors" was published almost a decade before any functional MOSFET was constructed.
> For designing MOSFETs, you just need to use classical electrodynamics, together with several functions that provide the semiconductor material characteristics, like intrinsic free carrier concentration as a function of temperature, carrier mobilities as functions of temperature and impurity concentrations (and electric field at high fields), ionization probabilities for impurities, avalanche ionization coefficients, dielectric constants, and a few others.
It sounds like you are describing what's required to parameterize some of the traditional semi-classical models of MOSFETs and understand the operating principles at that level.
but FETs work by bending the energy levels of the conduction band so there needs to be a band to bend, and if there's no band gap at the fermi level you can't have a FET, which makes it seem pretty dependent on quantum effects to me even without going deeper than necessary to understand how it can work.
Maybe one could have been engineered with no idea why silicon has the special material properties that it does and why doping changes those properties but AFAIK it never was, and being able to explain and understand band structure seems pretty important to build a working device.
The transistors described in the patents, i.e. MESFETs and depletion-mode MOSFETs were perfectly functional as described.
However, before WW2 one could have made such transistors that worked only by great luck, and they would have stopped working soon after that.
The reason is that before WWII it was not understood how greatly the properties of a semiconductor device are influenced by impurities and crystal defects.
During WWII there was a great effort to make semiconductor diodes for the high frequencies needed by radars, where vacuum diodes were no longer usable.
This has led to the development of semiconductor purification technologies and crystal growing technologies far more sophisticated than anything attempted before. Those technologies provided high-purity almost perfect germanium and silicon crystals, which enabled for the first time the manufacturing of semiconductor devices that worked as predicted by theory.
The publication of Shockley's theory has been necessary for the understanding of the devices based on carrier injection and P-N junctions, like the BJT and the JFET invented by Shockley.
However you can do very well electronics using only devices that are simpler conceptually, e.g. depletion-mode MOSFETs, Schottky diodes and MESFETs, for whose understanding Shockley's theory is not necessary, which is why they were reasonably well understood before WWII.
Before WWII the problem was not with the theory of the devices, but with the theory of the semiconductor material itself, because a semiconductor material would match the theory only if it were defect-free, and no such materials were available before WWII.
Before having such crystals, making semiconductor devices was non-reproducible, you could never make two that behaved the same.
"FETs work by bending the energy levels of the conduction band" is something used in textbooks, together with some intuitive graphs, with the hope that this is more intelligible for students.
I do not think that it is a useful metaphor. In any case this is not how you compute a MOSFET. For that you use carrier generation rates, carrier recombination rates, carrier flow and accumulation equations.
Instead of mumbo-jumbo about "band bending", it is much simpler to understand that a MOSFET is controlled by the electric charge that is stored on the metal side of the oxide insulator. That charge must be neutralized by an identical amount of charge of opposite sign on the semiconductor side of the gate. Depending on the sign and magnitude of that electric charge, it will be obtained by various combinations between the electric charges of electrons, holes and ionized impurities, which are determined by a balance between generation and recombination of electron-hole pairs and transport of electrons and holes to/from adjacent regions.
All the constraints lead to a unique solution for the concentrations of holes and electrons on the semiconductor side of the gate, which may be higher or lower than when there is no charge on the gate, and which may have the same sign or an opposite sign in comparison with the case when there is no net charge on the gate. This change in the carrier concentrations can be expressed as a "band bending", but this, i.e. the use of some fictitious potentials, does not provide any advantage instead of always thinking in carrier concentrations. (The use of some fictitious potentials instead of carrier concentrations had a small advantage in computations done with pen and paper, but they have no advantage when a computer is used. The so-called "Fermi level" is not needed anywhere, it just corresponds to the rate of thermal generation of electron-hole pairs, which is what is needed.)
Traditionally I don't think it was considered to be specially a quantum effect. That, again was because bipolar transistors specifically work over a quantum band gap ... and bipolar transistors proceeded mosfets.
So only a quantum effect to the extent all effects are at some level quantum.
Are these instances actually funded by 2021 IIJA BEAD program?
I don’t think Illinois has actually awarded any of that funding to providers to build anything yet. It looks like the original schedule was to start awarding grants this summer after planning process from 2021-2025.
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