dfox

70 ms·

781.
by dfox 7y ago
As for foot note 3: I suspect that reasoning for mostly not using TTL inverter chips in eastern designs was limiting number of BOM entries and number of chip designs that have to be manufactured in large volumes. Another thing is that in ma
782.
by dfox 7y ago
On high-end-ish switches that are truly designed for this application. And having switchable fans will not help you with device that has left-to-right (or even more weird) airflow.
783.
by dfox 7y ago
Most rackmount switches are not really designed to be used in datacenter rack as they do not have front-to-back airflow (and even if they would have, networking hardware tends to have all connectors on wrong side of the box). But almost eve
784.
by dfox 7y ago
I have one issue with or maybe just question about this graph. Why it starts with 100 detected cases? It seems like arbitrary round number, but it also seems to be the smallest arbitrary-looking number that makes SK overlap other countries.
785.
by dfox 7y ago
And in EU the whole 915MHz ISM band simply does not exist and is “the original GSM band” with the added caveat that there are some safety critical services inside the GSM's uplink/downlink guard band.
786.
by dfox 7y ago
You have to look at the issue from the organizer PoV and not as the event goer. You need to have some kind of reliable communication channels for the staff. The result of 10 years of experience of trying to cause that is for me that analog
787.
by dfox 7y ago
LoRa has very peculiar modulation scheme that in the end is not CDMA-ish spread spectrum but an interesting way how to extend straight FSK into spread spectrum modulation with respectable processing gain and interference rejection.
788.
by dfox 7y ago
And for the idea of doing RF magic for RFID: you to some extent want to do that, ant then you will find out that random Chinese sector antenna solves the same problem (obviously with the fact that it is simply not practical/possible to
789.
by dfox 7y ago
The simple solution is to simply make the customer to scan the item when they put it into the basket. It might be somewhat counterintuitive but in the end it makes better read rate. The amazon thing is obviously based on computer vision whi
790.
by dfox 7y ago
In fact US Army did design nuclear reactor that can be shipped in two 4TEU intermodal containers (design of the thing is highly RBMK-ish) and then managed to deploy that and cause nuclear accident with casualties(in the sense of personnel b
791.
by dfox 7y ago
Counting the DRAM row buffer as a separate cache layer is interesting because it has meaningful performance impact, but mainly because existence of such an thing is good counter argument to people who think that DRAM chips have RAS/CAS
792.
by dfox 7y ago
Doing it with RFID is surprisingly non-trivial even in the physical sense. That is the error rate of RFID bulk reads is small enough for opportunistic tracking of stuff, but mostly unacceptable for basing any kind of financial transaction o
793.
by dfox 7y ago
The reason why mainstream DRAM interfaces are narrow and “slow” is that you need row-at-a-time access patterns to really saturate the interconnect which is something that does not happen for general purpose workloads and causing such access
794.
by dfox 7y ago
IBM started to market what is essentially z with only IFL CPs as kind of k8s in a box so they obviously try to expand into lower tier markets.
795.
by dfox 7y ago
If you want truly secure format for these kinds of applications the best thing you can do is to sign the data externally (or wrap the whole file in some signed container, which seems to be the preferred solution for EU's EIdAS and rela
796.
by dfox 7y ago
The set of ~8 undocumented but well-known i386 instructions predates not only 9/11 but even 486.
797.
by dfox 7y ago
Today having physical copy of TAOCP is mostly only useful as the coffee table/conference room artifact. All the stuff in there is either well known because it is part of basic CS curriculum, better analyzed by subsequent works or mostl
798.
by dfox 7y ago
Or even do RPC calls in both directions over one stream socket... essentially all the “inflexible” RPC protocols of 90's can do that (and incidentally the way how this is implemented usually involves nested event loops)...
799.
by dfox 7y ago
It is. And in practice it is far from everything, only stuff that is actively directly referenced by the service code.
800.
by dfox 7y ago
The takeaway should be: don't do green threads/event loops for anything that involves any kind of non-trivial processing or even better yet, don't do that unless you really need to do such things (and “better performance” is
801.
by dfox 7y ago
And well the whole Trusted Platform Architecture is simply about having some kind of root of trust implemented by external chip that maintains set of hashes of what the hell runs on the platform and has physical GPIO ports to ascertain user
802.
by dfox 7y ago
For modern hard drives the head actuator is linear motor made from permanent magnet(s) and solenoid. the arrangement is called voice coil, because it is mostly the same thing as coil of an speaker (although the geometry is 90 degrees rotate
803.
by dfox 7y ago
There are two reasons why you would ever want to use something more complex: determining when the triggering happened (ie. who to blame) and ascertaining after the fact whether the trigger event was really meaningful for the package content
804.
by dfox 7y ago
Obviously there aren't similar issues with parsing JSON. On the other hand if you ingest XML you simply don't want to use full implementation of validating XML parser, because making that work is bunch of pointless busywork. And t
805.
by dfox 7y ago
In fact if you want to specify some kind of rigid schema (and for SOAP/XML Schema it usually is needlessly rigid) you are reinventing either ASN.1 or SunRPC's XDR, only with larger overhead...
806.
by dfox 7y ago
The reason why you cannot keep induction stove indefinitely on the highest power setting usually is that the cooling solution of internal electronics is not designed to reliably dissipate the maximum power loss continuously (it is similar i
807.
by dfox 7y ago
15 years ago I have observed that gcc on i386 would optimize away unnecessary steps of 64bit multiplication so one would assume that it is capable of doing the same for 128bit multiplication on 64bit platform and that thus it is not exclusi
808.
by dfox 7y ago
I think you kind of hint at interesting point: given how last few generation of iPhones are constructed (and that most current android phones take similar approach) it would be actually not that hard to make battery truly user replacable wi
809.
by dfox 7y ago
It can be just that simply your stainless steel cookware simply is not magnetic as opposed to having aluminium bottom, as about half of all stainless steel alloys are in fact not magnetic. On the other hand it infuriates me that the cookwar
810.
by dfox 7y ago
I still think that original Excel macro language was better than VBA. It essentially excel's formula language extended to be imperative language and represented as sheets. At the same time it was user friendly and had kind of lisp feel

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