Yeah I think it'll be location dependent. FWIW I've got both by me and they're equally terrible as far as the availability and knowledge of their employees. Lowes edges out Home Depot a tiny bit for me simply because I've never been accosted by a sanctioned in-store roaming sales person for solar or siding at Lowes (yet!).
I get hit up for gutter guards every trip at my Lowe’s. I have a stationary woman hawking Generac and HVAC installs at my Home Depot.
I’d agree though, it’s department dependent. The electrical at my HD is an unorganized mess, but their plumbing section is world-class. Lowe’s is oddly flip-flopped. To Lowe’s great credit, their staff has those little tablets with inventory locations on them including all the top-shelf and end cap locations the website doesn’t show. Those usually save my trip, HD doesn’t seem to have an equivalent.
I've found it to be very datetime dependent. I walking the aisles on a late Sunday night recently and the only time I saw an employee was at the self checkout before I left.
It's important to note that this is just Airbus's best guess as to the cause, as there's no smoking gun: they simply exhausted their troubleshooting and were left scratching their heads so this was the "least unlikely" cause they could come up with given the circumstances.
I thought the same, but in a deeper dive into the postmortem, I think it's not a cop out from their side. The report is actually really well done ( I personally was impressed). The reasons it probably was a bit flip is that the CPU did not have edac on it in this instance so bit flips are expected. The consensus mechanism failed in this case and that is what they are updating, because even though the module gave wrong data because of presumably bit flips, the consensus should have prevented the dive.
Not going to happen. The potentially huge cost to their reputation alone makes it not worth it, the modification would cost money and make logistics more difficult, and the plane couldn't be used (or sold) worldwide anymore.
Sorry, I didn't mean to be taking shots at any airplane company. I just disagree that multi-module consensus
is a reliable form of EDAC. I gave a human factor example, but there are technical reasons too.
> I just disagree that multi-module consensus is a reliable form of EDAC.
I wonder why you disagree about this? The only reason I can thing of is:
- same sw with same hw with same lifecycle would probably have the same issue. (vendor diversity would fix this)
- The consensus building unit is still a possible single point of failure.
Any other reasons you might doubt it as a methodology? It seems to have worked pretty well for Airbus and the failure rate is pretty low, so... It obviously is functional.
Modern units I'm sure have ECC, AND redundace as well.
Yes exactly, birds of a feather fail together... an A380 has three primary flight control computers, but still carries another entirely dissimilar set of three flight control computers as backup.
Well, the diversity would cover the issue with random HW failures, not the case your SW has a bug in it. As to the SW, they _sometimes_ have vendor diversity.
Regardless, there are multiple fronts you need to tackle to have high reliability so you should use all techniques at your disposal.
Until relatively recently, ECC on server RAM was because of chip failures and to lesser extent electro magnetic interference.
Good part selection and different EMI environment meant the calculated risks from not having ECC were considered too low to care and the idea that they might have to deal with radiation outside of flying near nuclear explosion arrived after the specific devices got designed.
Isn't a major feature of consensus algorithms for them to be tolerant to failures? Even basic algorithms take error handling into account and shouldn't be taken out by a bit flip in any one component.
Yes. To clarify, my understanding of _this_ particular incident was wrong because it was based on reading the report of a previous incident.
But for the 2008 incident I read and linked the report, that was what happened. The ADIRU unit did probably get a SEU event and that should have been mitigated by the design of the ELAC unit. The ELAC unit failed to mitigate it so that's the part that they probaby fixed.
My reaction was initially that it was a cop out, but looking a bit in the report and thinking things through, I think that, yes, it's most likely a bit flip.
You've reminded me of the hellscape of Microsoft's "help" forums filled with people asking specific questions and getting their question closed with a barely-relevant response followed by many others commenting, essentially, "me too! why won't anyone help us?"
I think we have a surplus of "awareness" tools/websites that are great at what they do, but not much "rubber meets the road" tools to guide the user in actually taking action based on the information presented. I, for one, feel a huge sense of fatigue at the amount of awareness I have of problems I don't have the tools/strategies/knowledge/time to solve.
(This is not a negative comment about this post btw, more just commentary on how the fire hose of "look at how bad this is in excruciating detail" can be overwhelming.)
Dubious or non-existent performance numbers, self-aggrandizing references to being in close contact with other, more famous/infamous CEOs/people, and the bluster of urgency as a smokescreen to hide the lack of anything concrete throughout- this Blake Scholl is following the Elon Musk playbook to a "T".
100%! I will always give the benefit of the doubt when I see odd syntax/grammar (and do my best to provide helpful correction if it's off-base to the extent that it muddies your point), but hit me with a wordy, em-dash battered pile of gobbledygook and you might as well be spitting in my face.
For a refresher: https://i.kym-cdn.com/entries/icons/original/000/033/037/gir...
reply