@edps
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Lets see if I can explain one of the most scary areas of AI — neural networks and why they are scary. I’ll probably fail, but I have warned you!
Imagine if you will a number of quite complex wiring blocks, but each has the same rough layouts with the inputs going in on A and the outputs on B. Lets imagine this is a sensor net in which the sensor inputs go from no input up to 100% with all the possible points in between. Lets also have the outputs run from undetected up to definitely detected with all the values in between. Easy so far so lets make the relationship non linear. In a military context this could be a PIR detector for an autonomous gun firing sentry.
Now we need to decide whether that was a leaf, rabbit or person, so feed in the output from the first layer into a second layer that detects the size of the object depending how many PIRs were simultaneously triggered and throw out (set to zero) all the little objects. Still easy and still deterministic.
Lets throw in a third vector and take that output and check in which direction the movement is going. Still easy and deterministic, so throw in the fog of war (some real fog), a PIR does not work very well in fog so results soddenly become vague and random. We so not want the sentry to go firing off its guns at random so we need to feed each of these results into a hidden layer that will mash them all together in some way that gives the results that best match practical experience. This puts a weighting on each of the various inputs and combines them to give an output, the weighting is found by training the neural net against many thousands of different atmospheric conditions and taking the results that fit our preconceptions of a most likely outcome. This was a simple example in a real world case there might be a fairly large number of hidden layers each with different weighting factors.
If you now try and figure out just why the ‘sentry’ fired its gun and killed your friend Joe you will get a ‘probably’ because of this and that, but the reality is that it is a ‘beats the crap out of me and, I can only give you a best guess as an answer’.
Its a bit like showing someone a shade of grey and asking if it is black or white. The question is inappropriate as the answer will be shaded by what do you mean by black or white, and all the external factors such as lighting etc.
Currently neural networks cannot give an understandable answer for why it comes up with a particular action. You have to trust that the programmer did not slide in a few biases (for example set that everything above the size of a small dog may be a viable target i.e small children are viable. You can also throw in biases during the classification of the many sets of training data.
In other words you have to have complete trust in a programmer, who if honest will still give a ‘beats the crap out of me’ response when asked ‘Why?’
I’ve horribly simplified my answer, a better response might be had by looking at this. (ignore the programming and concentrate on the pics and headings to possibly get a better over-view.)
As far as I can tell the process I posted previously works on all makes of Pi and is fairly robust in that the SD card is only used at boot. It also seems to work on every drive I’ve used. i.e. it is fairly safe bet, but perhaps not the best if you have a Pi 3B.
Swappiness is a different issue – I do not know if anyone has access to the old MM files but there was a thread on that in which iirc Bruce showed a very substantial usb R/W performance improvement by reducing the swappiness to 5. (Caused I think by a unfriendly embrace between the needs of file access and page file swaps taking place on the same, not very efficient, drive). In server use swappiness is set to 60-100 (default 60). I’m not sure what I would use for a NAS. Backup is essentially a swappiness 5 operation, while simultaneously playing media files is possibly a 10. As swappiness is a reflection of reusing page files I think you probably only really need to increase it for the case of concurrent users. Wiki type info here
No but if you are setting something up for a third party then I’d recommend the 3B+ for that reason as well as a marginally faster wifi/ethernet.
Further my previous note, I was trying to figure out why you were finding USB boot hard. The only thought I had was that maybe you had an early crib sheet. This link gives what I think is a simple set-up.
If you read through the 21 pages of this thread you will hit this nugget of info:
“… The only change I know about is that the Pi3B+ is set up to boot from USB (or PxE) by default. I got a Pi3B+ yesterday and within 5 minutes of opening the package, I had it booted from a PiDrive by swapping it in to replace a Pi3B. No muss, no fuss.
(And is response to some non-current, but still moderately recent posts…the Pi2Bv1.2 should be able to have the OTP bit set and boot from USB. The ability is a feature of the ‘2837 SoC and is therefore, board independent. …)”
My only thought of difficulties applies to Pi2s or PiZero that have different chipsets and also ‘pickey’ usb drives. There the boot from SD with kernel on usb drive is the best route, and very simple to do, but I’ll post something on this later as I have to go out.
According to this link HyperV’s Remote Fx is also a bit of a Curate’s Egg for GPU passthrough. (Not a true transparent passthrough). For me it would offer no more than does VMWare, and possibly less.
This quote says it all:
“I would not get excited that you can now start running a bunch of 3D games in Client Hyper-V. That’s not really what RemoteFX is for. A game might work, but it might not. More “run-of-the-mill” applications, like web browsers and operating system GUIs are incorporating 3D, and that’s where you’ll see the most differences with a RemoteFX adapter. As you can see in Device Manager, you’re not getting a direct projection of your video adapter, which means that you’re not going to be able to load the manufacturer’s specific hardware driver, which means that you cannot expose its full capabilities to the guest.“
Dave it is not as hard as it looks, but using a SD->HDD handoff is trivial. I guess the really important part for a NAS is the location of the swap file, and the other files of course.
Lord I haven’t been to Barry Island since I was 8! Southerndown and the Ogmore Valley were much nicer.
Looking at the pics, Southerndown has lost a lot of sand since my childhood.
I case it was not clear the buildings in question were ruined and the same ones shown (without the passers-by) by the Beeb!
My comments do not mean that I believe the Russians more than HMG. Just that HMG is acting suspiciously like this was all a White-Hat/rogue CIA plant.
Steve, I don’t even need to do any programming as Minecraft is already part of the Pi package. I understand that Minecraft is actually used as a teaching aid in many schools so I may throw in a script with an ‘instant’ log cabin or one of the examples here.
The P in EdP stands for Plagiarism as I do a lot of it in my programming!
Thanks for the link – it raises a lot of other possibilities and I may well use one for my school’s demo. (not as a NAS!)
I don’t think anyone involved or watching liked seeing horses killed, but it is a fact that a broken leg for a horse is still near impossible to repair at this time and too great an emotional trauma for any horse. (In another 10 years stem cell/bone rebuilding tech just might make it viable).
Putting the very demanding Aintree Course aside for a minute, hunters and steeple-chasers actually like jumping and racing, and some horses are quite competitive even without a jockey (just watch some of them jump the fences when they have lost their jockey).
The debate should not be over whether Hunt or steeplechase races are evil, but whether Aintree is too demanding. I’m pretty sure that any accidents on the course will be thoroughly investigated and further steps will be taken to reduce the future probability of such accidents. IMO no-one will have viewed Aintree as a gladiatorial event in which humans and animals are killed and injured. Apart from actually liking their animals, the cost of ownership and upkeep/training of a horse are far too high for any owner to lightly throw away any horse’s life just for public entertainment.
Thanks Dan – looks nice. I might get one for myself, use it for demo purposes and say cheaper/smaller options such as the Huon 420 are available. I’ll price up both options.
Life for teachers and Heads is a bitch around here. They have so little cash Primary Schools even have to ask for help to put in new Whiteboards.
You can add to that the apparent abduction and holding incommunicado of one of the victims. I’ll be much happier if she is allowed a live TV interview with a respected (Swiss) journo who promises not to stress her out too much.
Am I suspicious of HMG — too darn right I am. There are too many factual and evidential holes in what has so far been reported or released to the general public. Even the poisoned policeman is puzzling – if the poison was on the door handle why the hell did he abandon normal police crime scene procedures and take his gloves off? As to Syria – that should be left to the OPCW including inspection of the so-called nerve gas centres. (One clip showed people wandering around outside the buildings in shirt-sleeves. — no sign of ANYONE in protective clothing).
I agree with your comment about Pi3+ and possible NAS usage but I hope that your blog will also include a direct boot from SSD. You really do not want any swap files trying to access the SD card as such cards have both a relatively short cycle life as well as being quite vulnerable to power outages, or crash shutdowns.
I also suspect that swappiness may be something worth investigating for NAS usage. Bruce did quite a thorough investigation of its impacts when he was looking at running Linux from a usb. The swappiness can make a substantial performance difference, but depends on how much concurrency is taking place. (I think you may even need to INCREASE it for a lot of concurrent NAS usage, whereas for single person use it can be close to zero.)
I should have said OPCW and probably given citations on legality.
I also said Libya was illegal, maybe it wasn’t even though it felt that way, but it was certainly stupid.
Sorry to disagree. Syria is a sovereign state and as such protected by UN conventions and we have not made a formal declaration of war. We did not allow due process on what looks like a ‘Jenkins Ear’ excuse for military action. We should have allowed the OCPW to have ruled on whether illegal WMD weapons were actually used and how were they delivered before taking action. As it is we could well find the OCPW discovers nothing and we will once again be guilty of an illegal war crime (Iraq and Libya were both illegal, and as subsequent events show stupid).
Now working fine for me too.
” The plan is to do a Windows VM on Linux…”
Depends what he wants to run. I have not yet found a transparent way of running anything that requires DirectX12. That rules out many modern games and some CAD/3D graphics stuff. DirectX 10 is all that is supported.
As a result I do it the Windows host with Linux VMs route, and feel let down by VMWare.
Hot war starts if another shoe drops.
For the time being I would expect Russia to appear statesmanlike,but it will need something for its home consumption e.g. bring its front-line planes back to Syria and ramp up Syrian air defences, and possibly joint military exercises/assistance with Iran.
I think its more damaging responses will be asymmetric and deniable. For example by sabotaging allied projects elsewhere in the world e.g. stir up Brexit problems by buying off a few people in the EU, cut cooperation in Afghanistan or Korea, stir up problems in Chad and Libya. All of a sudden we could find our hands very full.
Block 3 testing for the Turkey has finished, but the US has suspended delivery which will mean further delays to the British version of the Turkey. We should however get deliveries before it is completely obsolete. Assuming that is, that the Block 4 testing goes better than that for Block 3, however as the above link hints the auguries do not look great.
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