IMHO virtually every (on topic) issue here is about implementation details. Sure any wireless mouse can lag if you develop it to be highly CPU dependent (currently running Fah with 100% CPU use and no noticeable difference in mouse tracking).
It's probably better to talk about specific models rather than talk about generic things like BT vs. prop wireless.
For example I use a Microsoft Wireless Notebook Presenter 8000. It seems to work flawlessly as a mouse - it's not really a great presentation tool though - although it is fun to have a laser pointer built in.
I bought it mostly because it is small and doesn't use a dongle (although it comes with one if you don't have BT).
It also seems resilient to ambient wireless noise. There is a bank of Macs in the hallway behind my office and I can see them all when I try to pair it (as well 802.11abg is running in the area).
I already had a few different machines in my house in 92-93. One was my first PC which ran windows 95 (and later NT4 when MS was giving it away with Visual Studio Tools). One was the PC I had just built. I was also in line to get hooked up to the new high-speed internet service called "Wave" (served over the CATV system). I had already seen hardware internet sharing devices for dial-up but they were very expensive. Some of my peers said that you could do the same thing with Linux.
So I bought a copy from FutureShop (Slackware 4.0) and started installing. I've been running a Linux box ever since.
> I'm not sure why you question my open-mindedness.
Again straight from several replies:
-Your commentary had little to do with my ethical position. -Your commentary was far more your opinion than questions about mine. -You have repeatedly conflated a number of issues.
> Obviously I have preconceived notions, but I did/do want to understand the other side of the story.
Not enough to give much of a response to items in my ethical statement but you have spent comparatively large amounts of time defending your manipulative statement and various other things. Yet each one of my responses draws attention to you not addressing the alleged original point about you wanting to understand.
Not enough to ask questions on the points you didn't understand or to be sure that you had them correctly.
Not enough to spend some time in self-analysis to see how you are mixing a few issues here.
>Not really thanks to you, since your comments aren't really constructive
I certainly think I've pointed out some of your errors repeatedly. Considering that much of the content in your other two replies were just droning on about your POV. If you had any questions about mine you failed to ask.
Calling people ignorant seems to make you feel smarter.
It doesn't really make me feel much of anything. It's just the facts as they appear to be. If you've got something to say about the very thing you asked for then do please share.
The "my kids can't eat" comment was a different way of saying that "I can't make a living if everyone infringes on my copyright."
So it was begging the question then? That still seems to fall into the 'ignorant' classification. Although in a slightly different way than I originally anticipated.
That seemed obvious to me, but maybe not to someone who's in a disagreeable mood (others interpreted it in the way in which it was intended).
For someone who seems to want to at least appear open-minded don't you think you're pigeonholing a little to early here? It seems that you didn't even understand my criticism let alone have enough information to post a cogent response.
I know, trying to see things from someone else's perspective is something that can get you banned from Slashdot so I should probably stop.
I doubt you can get banned strictly for what you claim. Your ignorant sarcasm paints a rather different picture than someone who is attempting to understand peoples ethical positions.
But I wouldn't have posted it if I didn't want to understand other people's perspective.
No offense but considering your response to mine barely even touched on my ethical position as well as your tireless speechifying and your need to conflate the issues. I'd say you aren't trying very hard at all.
But hey, as you've already illustrated you can just rationalize everything by saying someone is in a bad 'mood' - I guess that's one way to avoid thinking about things.
It was manipulative in that I wanted to elicit a response, which I did.
The only part of the response that you can reasonably attribute to your manipulation is that part that said you were being manipulative and/or ignorant. Is this somehow smart on your part?
Without financial incentive, there will be less innovation.
Is this more manipulation? Was the so-called sincere request for a discussion on ethics actually a lead-in to discuss an orthogonal issue?
Because again, you come off here like you either didn't read or understand my post. Hopefully ignorance and manipulation isn't a theme for you (or with your customers).
I don't really see why this would seem mysterious to you. Clearly people consider the perceived benefit less than the perceived harm.
As to why?
For me I remain unconvinced of your seemingly implied assertion that a significant portion of piracy represents a lost sale nor do I see any reason to believe that allowing this mode of piracy as having generally significant negative social repercussions.
Now those may in fact be the case but until I see significant statistical data I don't see why your belief trumps mine.
And since I also doubt that you possess such information your "my kids can't eat" statement comes across as either ignorant, manipulative or both.
Conversely it is, at least arguably ethical for me to use a torrent to get a copy of something I already have purchased. I would say that this constitutes the vast majority of my use of software torrents. The next biggest case is likely when I am attempting to answer a question (for example about requirements like compatibility or scaling) for which the vendor is simply too thick to answer.
Nothing wrong with NX/ASLR. Except perhaps as support to the claim that windows is "safest os on the planet" or some such nonsense. We have been using GrSecurity since long before Vista was out. Which makes the interviewer's "Vista-like-ASLR" kind of an odd quality for something to posses. If anything it's Unix-Like ASLR.
Furthermore, and I don't know if this is patched in later versions of Vista but the author also seems confused about the implied "nobody knows how to defeat ASLR under windows".
Do you mean it's a formal fallacy? If so, which one?
Personally, I'd say it has a couple of implied assumptions but they are hardly uncommon and I'm unconvinced they they are somehow disprovable. I'm not even convinced this is an implied argument.
For example if you interpret the statement to mean:
It is significantly easier to treat a laudable person well than one who does things that their society consider very bad. It is more likely to see problems by observing how they treat the later than the former.
The issue comes with the idea that that it's being posed as an "value based" argument rather than a statement of fact. An "ought" rather than an "is". This would be, imho a fallacy if it was being stated as "Because this is an *is* it is also an *ought*" however it seems like you could just as easily read this as a statement, not an argument.
... I still find the implication that current medical treatment does not apply these standards as heartbreaking.
Also from the link:
Evidence-based medicine (EBM) aims to apply evidence gained from the scientific method to certain parts of medical practice. It seeks to assess the quality of evidence relevant to the risks and benefits of treatments (including lack of treatment).
...and some stuff about the ranking of evidence, recommendations and statistics.
So it was your apprehension that medicine over the past decade or so generally applies the significant majority of these concepts?
makes it seem like the use of evidence is not used.
To you, but remember this is the subgroup of people who are unable/unwilling to consider their knowledge of a term significantly incomplete enough click a link and at least pry open their minds wide enough to determine (even simply by the size of the article) that the idea isn't the same as "having some usage of evidence".
I'd expect those principles generally applied earn you a lot of misapprehension though.
Won't even get into people who complain that someone isn't being clear and then uses 'implies' when 'I would infer' is clearer.
But, I think you're right. If I'd wasted the time to read the extensive article,
or even looked at it in order to determine this was more than just "having some usage of evidence".
Is that article really about an idiom?
It should convince you that it's more than the literal reading and some of which should convince you that it would be highly improbable to deduce from it. QED.
I don't have time to read all of it.
Perhaps you can re-allocate some of your "ignorant spouting off" time?
Then, unless they are going to keep 'shop talk' in the shop, they need to use clearer idiomatic expressions
Your commentary is misplaced I don't see anywhere in the linked article where EBM is even mentioned. It's only in the slashdot posting which does not appear to be written by a doctor. Ergo this isn't about someone's shop talk. As mentioned earlier the correct definition was linked to.
Not to mention that the definition of an idiom is something that can't be derived from the conjoined meanings of it's elements. How could you make that clearer? Other than...say...linking to a definition?
Again try, try to accept that you are the idiot here. It's healthy.
Your interpretation seems to be completely literal which makes your argument appear to be "they shouldn't use idioms".
In any case nobody forced any non-doctor to use the term. Nobody forced the writer to skip their fact checking in this respect and lastly nobody forced you to used the term as if you understood it.
Next time try blaming yourself rather than others.
ugh....why do people make the same mistake all over. "Evidence Based Medicine" isn't meant to imply that all other medicine did not use evidence or even good evidence. It's an *idiom* from crying out loud representing a number of things that Sackett and others considered wrong with medical practice. One of which is there was not a standard for interpreting and ranking evidence in medicine.
By "lose" I mean your argument about me being evasive.
My argument is there, plain to see - if you have a counter please state it. A clear and concise statement of your position is nowhere to be seen - still.
All you had to do was state your argument clearly and then it could be discussed. However you avoided every opportunity to do so. If you had a cogent argument (or a disproof of mine) one would assume that you would have stated it by now.
On the other had I stated my position at length AND answered your most recent question to the best of my knowledge.
See, that's the difference between you and I. You see (or rather, hear) a noisy data center, and assumes that it's the same inside the actual chasis.
Don't mistake my beliefs with outlining the assumptions you need to make your religious system work.
Whereas, I believe (since I've not actually researched this, and only know about it second hand) your SAN units have actually have vibration dampeners designed in.
That's actually irrelevant. So you are confused about something but it's unclear exactly what.
go ahead and say Apple charges 130% extra for their special rubber grommets.
That's also irrelevant to the discussion. Apple is charging for a lot of things (branding for example) the article is talking about the comparative value of taking an ADM and then stripping out the drive and replacing it with a non-Apple drive. So the only vibrational difference outlined here is "the rubber grommets that hold the drive to the ADM carrier" and the reason give is that they "are chosen specifically to match each drive's vibrational characteristics"
So I asked the all important question "So what" about "if the drives vibrational characteristics are not matched" (via these special grommets)
And you made some obtuse reference to the JBOD / Dtrace clip that's been going around everywhere.
Again you have avoided a simple and incredibly direct question. All you needed was to say yes or no but you couldn't. If you state your argument clearly:
i.e. Burn-in testing is useful for most people because it would catch at least one in twenty drive failures this is based on the 6% AFR figure for one month.
Then I could get around to actually showing you why you are wrong. When you keep beating around the bush and then make (ill-informed and illogical) accusations when someone asks you what you actually need explained. It's going to be difficult showing you where you are wrong. However I expect that's what you want.
I've already stated what I believe but here it is again for the record: Apples burn-in testing does not add significantly to failure prevention compared to drives purchased over-the-counter. I expect that we are looking at something close to a failure detection rate of no better than an average risk of 1 in 300 to something worse that 1 in 500. Which is hardly a significant risk in buying a single drive for an x-serve or a set of drives for an Xraid (conflating both my example and the articles examples). Furthermore even if that is a risk, it's only a service of value to those way outside of the articles target audience.
So what is the difference between the compute and the file system nodes - no more weaseling around.
Again, I'm stuck decrypting your statements into an actual argument. So what do you want here? Personally I see little that can be definitively stated as a difference between the systems (the type of drive use could be inferred). That said there is little reason to believe that the failures shown in the first month of compute node usage are important to a *general* - This is an important word - argument which is what you appear to be making.
either you are stupid, or you know you are wrong and are being evasive...or whatever your assertion is it's wrong and I've already dismissed it and as a result you are forcing me to pick amongst wrong ideas (which there are significantly more than right ideas)....or I've already addressed it (i.e. references to selection bias and you getting to pick and choose the data post hoc) and you don't yet understand why that is wrong.
There could be other options but all I need is one to show that your argument about me being "either X or Y" as false.
So am I to infer here that you are referring to the fact that at 1 month, the AFR reaches 6% on HPC 1's compute nodes in the first month and are implying that this says something generally about stress testing utility?
Just say if this is the case or not...and I'll explain the problem with that - no offense but considering how evasive (and illogical) you are being. I'd like to actually pin your argument down before I destroy it.
Where did I complain that Apple does burn-in testing? That's right, nowhere.
I did complain that the article asserted Apple's doing of this as valuable and beneficial and that the largest body of data does not bear out the later.
You're still being pretty evasive about what exactly you want explained.
Are you struggling to say that when you pick a portion of a dataset post-hoc it does say there's something beneficial about burn in testing?
Also, do get an engineering degree while you're at it.
Is that what you have? If so thanks for making the fight against prejudging engineers as mathematically ignorant and devoid of proper experimental methodology just that much harder.
The truth is you could have five hundred billion articles on vibration affecting (in some way) drives. However that doesn't mean:
a) That constant shouting has the same effect. For example one of my datacenters is easily loud enough that one has to shout to be heard. Are the SAN units in there constantly having higher latency. Why didn't we see a benchmark difference between inside and outside?
b) That the effect is uniform across all devices. c) That the vibration from HD's in action is somehow comparable. d) That this can be fixed with little rubber grommets. e) That Apples little rubber grommets can fix them.
See the thing that you are clueless on. Is that all you have is evidence that some kinds of vibration on some systems in some environments cause some kinds of problems. However the argument you are feebly attempting to counter is that Apple's little rubber grommets actually help in some significant way.
This leaves out the most important thing. "So what" - ok if the drives vibrational characteristics are not matched what happens. Is it significant? Where is the data to say so?
In high capacity drives, vibration is a huge factor. Did you not see the youtube video of someone screaming at his drives? It got posted on slashdot.
I love statements like "huge factor" - I suspect this is what I refer to as "adjectives over evidence". Your need to use an adjective like "huge" stems from your inability to actually quantify the risk.
Yes I saw the videos. I'm wondering how much you actually thought about them though. They show someone shouting at a disk array and an increase in latency as an apparent result.
But MY statement was "Do we really need special grommets to match the drives vibrational characteristics and if so what do we lose?"
Do you not see how someone shouting at a specific disk array doesn't necessarily disprove that statement (or prove your general statement)?
In case your answer is "no". Here is a handy list of things you would need to demonstrate to get to disproving my statement from yours.
i) Constant shouting causes equal and constant impact. From the video it looks like the shouting results in an big effect on latency. However it's hard to tell how long that effect would last if the shouting was constant (this is closer to the idea of using different grommets like Apple suggests).
ii) Shouting at an x-serve (or x-raid) makes a difference. See you can't assume that one data point makes the case for all data points. This is what Sacket referred to as the disastrous inadequacy of lesser evidence. For example perhaps the Sun box is so well engineered (compared to the X-Serve) that it's one of the few that actually ALLOWS this to happen.
iii) Having specific grommets can actually make a difference. Grommets beyond a base tolerance may not make a difference. Perhaps the kind of vibration that most grommets allow is not the kind that makes a difference in latency (maybe it's about frequency, maybe it's about amplitude).
iv) Once we establish that it's possible for screws to make a difference. It still remains to be proven that APPLE's grommets make a difference. Perhaps the only kind that make a measurable difference cost $1,000,000,000 grommets and are fashioned by elves or something
v) Apples grommets make a SIGNIFICANT difference. Just because screws make a measurable difference it doesn't mean its going to be one that most sysadmins care about.
The original drives were functioning up until we replaced the lot. The replacement was for capacity.
"you've yet to state anything of any usefulness in the comparison"
Note that this was an incidental note not a counter-argument to the idea that there is significant risk. I already addressed the alleged differences between Apple and non-apple drives in my earlier post. We did in fact add one thing to the conversation that the install was trivial and the only firmware issue was with the XRaid itself.
"there is still time for it to fail"
Clearly and even if these drives last as long as the other drives did it still wouldn't say anything meaningful (well it might cause you to doubt your idiot premise). Point being that you actually need a large sample size. Which I touch on in my earlier post.
"using cheap drives its very rarely actually worth it."
Again the largest bodies of data do not support this assertion. Enterprise drives and non-enterprise drives show little in the way of difference in terms of replacement rates. I've already posted links to the FAST study. So either there is no difference or the difference is overshadowed by other factors or this is something that only affects the very specific drives Apple is talking about.
Did you even READ the article most of the alleged differences strain credibility.
Incidentally: Our dept actually did a similar kind of upgrade on an XRAID (which was PATA but Apple had made all sort of claims: 'zero defect drives' blah, blah, blah). It's been working fine for close to a year now. The only issue was a firmware upgrade (to the XRAID) to handle the 750GB drives which would have had to be done even if we bought Apple. The cost savings was pretty significant I recall - something like 60% of the Apple price.
This was a complete replacement though. I do agree with one admins posting above though that if you are replacing a single drive then you need to be careful (and spend the money) to insure that the replacement is an exact match.
Slashdot Mirror
IMHO virtually every (on topic) issue here is about implementation details. Sure any wireless mouse can lag if you develop it to be highly CPU dependent (currently running Fah with 100% CPU use and no noticeable difference in mouse tracking).
It's probably better to talk about specific models rather than talk about generic things like BT vs. prop wireless.
For example I use a Microsoft Wireless Notebook Presenter 8000. It seems to work flawlessly as a mouse - it's not really a great presentation tool though - although it is fun to have a laser pointer built in.
I bought it mostly because it is small and doesn't use a dongle (although it comes with one if you don't have BT).
It also seems resilient to ambient wireless noise. There is a bank of Macs in the hallway behind my office and I can see them all when I try to pair it (as well 802.11abg is running in the area).
I already had a few different machines in my house in 92-93. One was my first PC which ran windows 95 (and later NT4 when MS was giving it away with Visual Studio Tools). One was the PC I had just built. I was also in line to get hooked up to the new high-speed internet service called "Wave" (served over the CATV system). I had already seen hardware internet sharing devices for dial-up but they were very expensive. Some of my peers said that you could do the same thing with Linux.
So I bought a copy from FutureShop (Slackware 4.0) and started installing. I've been running a Linux box ever since.
The writer of the article response to Lori's claims
http://o3magazine.blogspot.com/2009/04/ssl-accelerator-strikes-nerve-with-f5.html ...and nails her on a few I'd say.
>Wow, you really do seem to enjoy disagreeing.
Less so than I enjoy agreeing.
> I'm not sure why you question my open-mindedness.
Again straight from several replies:
-Your commentary had little to do with my ethical position.
-Your commentary was far more your opinion than questions about mine.
-You have repeatedly conflated a number of issues.
> Obviously I have preconceived notions, but I did/do want to understand the other side of the story.
Not enough to give much of a response to items in my ethical statement but you have spent comparatively large amounts of time defending your manipulative statement and various other things. Yet each one of my responses draws attention to you not addressing the alleged original point about you wanting to understand.
Not enough to ask questions on the points you didn't understand or to be sure that you had them correctly.
Not enough to spend some time in self-analysis to see how you are mixing a few issues here.
>Not really thanks to you, since your comments aren't really constructive
I certainly think I've pointed out some of your errors repeatedly. Considering that much of the content in your other two replies were just droning on about your POV. If you had any questions about mine you failed to ask.
Calling people ignorant seems to make you feel smarter.
It doesn't really make me feel much of anything. It's just the facts as they appear to be. If you've got something to say about the very thing you asked for then do please share.
The "my kids can't eat" comment was a different way of saying that "I can't make a living if everyone infringes on my copyright."
So it was begging the question then? That still seems to fall into the 'ignorant' classification. Although in a slightly different way than I originally anticipated.
That seemed obvious to me, but maybe not to someone who's in a disagreeable mood (others interpreted it in the way in which it was intended).
For someone who seems to want to at least appear open-minded don't you think you're pigeonholing a little to early here? It seems that you didn't even understand my criticism let alone have enough information to post a cogent response.
I know, trying to see things from someone else's perspective is something that can get you banned from Slashdot so I should probably stop.
I doubt you can get banned strictly for what you claim. Your ignorant sarcasm paints a rather different picture than someone who is attempting to understand peoples ethical positions.
But I wouldn't have posted it if I didn't want to understand other people's perspective.
No offense but considering your response to mine barely even touched on my ethical position as well as your tireless speechifying and your need to conflate the issues. I'd say you aren't trying very hard at all.
But hey, as you've already illustrated you can just rationalize everything by saying someone is in a bad 'mood' - I guess that's one way to avoid thinking about things.
It was manipulative in that I wanted to elicit a response, which I did.
The only part of the response that you can reasonably attribute to your manipulation is that part that said you were being manipulative and/or ignorant. Is this somehow smart on your part?
Without financial incentive, there will be less innovation.
Is this more manipulation? Was the so-called sincere request for a discussion on ethics actually a lead-in to discuss an orthogonal issue?
Because again, you come off here like you either didn't read or understand my post. Hopefully ignorance and manipulation isn't a theme for you (or with your customers).
I don't really see why this would seem mysterious to you. Clearly people consider the perceived benefit less than the perceived harm.
As to why?
For me I remain unconvinced of your seemingly implied assertion that a significant portion of piracy represents a lost sale nor do I see any reason to believe that allowing this mode of piracy as having generally significant negative social repercussions.
Now those may in fact be the case but until I see significant statistical data I don't see why your belief trumps mine.
And since I also doubt that you possess such information your "my kids can't eat" statement comes across as either ignorant, manipulative or both.
Conversely it is, at least arguably ethical for me to use a torrent to get a copy of something I already have purchased. I would say that this constitutes the vast majority of my use of software torrents. The next biggest case is likely when I am attempting to answer a question (for example about requirements like compatibility or scaling) for which the vendor is simply too thick to answer.
Nothing wrong with NX/ASLR. Except perhaps as support to the claim that windows is "safest os on the planet" or some such nonsense. We have been using GrSecurity since long before Vista was out. Which makes the interviewer's "Vista-like-ASLR" kind of an odd quality for something to posses. If anything it's Unix-Like ASLR.
Furthermore, and I don't know if this is patched in later versions of Vista but the author also seems confused about the implied "nobody knows how to defeat ASLR under windows".
http://blog.trendmicro.com/flaw-in-windows-vista-aslr-implementation/
Under PaX Linux has far more randomization than that.
Do you mean it's a formal fallacy? If so, which one?
Personally, I'd say it has a couple of implied assumptions but they are hardly uncommon and I'm unconvinced they they are somehow disprovable. I'm not even convinced this is an implied argument.
For example if you interpret the statement to mean:
It is significantly easier to treat a laudable person well than one who does things that their society consider very bad. It is more likely to see problems by observing how they treat the later than the former.
The issue comes with the idea that that it's being posed as an "value based" argument rather than a statement of fact. An "ought" rather than an "is". This would be, imho a fallacy if it was being stated as "Because this is an *is* it is also an *ought*" however it seems like you could just as easily read this as a statement, not an argument.
I generally drink 2L of diet cola per day.
That's around 200mg/day. I generally don't drink on weekends and I've not really noticed withdrawal symptoms.
Mind you it could be masked by my sleeping more on weekends.
... I still find the implication that current medical treatment does not apply these standards as heartbreaking.
Also from the link:
Evidence-based medicine (EBM) aims to apply evidence gained from the scientific method to certain parts of medical practice. It seeks to assess the quality of evidence relevant to the risks and benefits of treatments (including lack of treatment).
So it was your apprehension that medicine over the past decade or so generally applies the significant majority of these concepts?
makes it seem like the use of evidence is not used.
To you, but remember this is the subgroup of people who are unable/unwilling to consider their knowledge of a term significantly incomplete enough click a link and at least pry open their minds wide enough to determine (even simply by the size of the article) that the idea isn't the same as "having some usage of evidence".
I'd expect those principles generally applied earn you a lot of misapprehension though.
Won't even get into people who complain that someone isn't being clear and then uses 'implies' when 'I would infer' is clearer.
But, I think you're right. If I'd wasted the time to read the extensive article,
or even looked at it in order to determine this was more than just "having some usage of evidence".
Is that article really about an idiom?
It should convince you that it's more than the literal reading and some of which should convince you that it would be highly improbable to deduce from it. QED.
I don't have time to read all of it.
Perhaps you can re-allocate some of your "ignorant spouting off" time?
The context they are used in makes a difference.
Like say when the proper meaning is linked to?
Then, unless they are going to keep 'shop talk' in the shop, they need to use clearer idiomatic expressions
Your commentary is misplaced I don't see anywhere in the linked article where EBM is even mentioned. It's only in the slashdot posting which does not appear to be written by a doctor. Ergo this isn't about someone's shop talk. As mentioned earlier the correct definition was linked to.
Not to mention that the definition of an idiom is something that can't be derived from the conjoined meanings of it's elements. How could you make that clearer? Other than...say...linking to a definition?
Again try, try to accept that you are the idiot here. It's healthy.
Your interpretation seems to be completely literal which makes your argument appear to be "they shouldn't use idioms".
In any case nobody forced any non-doctor to use the term. Nobody forced the writer to skip their fact checking in this respect and lastly nobody forced you to used the term as if you understood it.
Next time try blaming yourself rather than others.
ugh....why do people make the same mistake all over. "Evidence Based Medicine" isn't meant to imply that all other medicine did not use evidence or even good evidence. It's an *idiom* from crying out loud representing a number of things that Sackett and others considered wrong with medical practice. One of which is there was not a standard for interpreting and ranking evidence in medicine.
By "lose" I mean your argument about me being evasive.
My argument is there, plain to see - if you have a counter please state it. A clear and concise statement of your position is nowhere to be seen - still.
Ahh...and you lose.
All you had to do was state your argument clearly and then it could be discussed. However you avoided every opportunity to do so. If you had a cogent argument (or a disproof of mine) one would assume that you would have stated it by now.
On the other had I stated my position at length AND answered your most recent question to the best of my knowledge.
So how does that make me evasive?
See, that's the difference between you and I. You see (or rather, hear) a noisy data center, and assumes that it's the same inside the actual chasis.
Don't mistake my beliefs with outlining the assumptions you need to make your religious system work.
Whereas, I believe (since I've not actually researched this, and only know about it second hand) your SAN units have actually have vibration dampeners designed in.
That's actually irrelevant. So you are confused about something but it's unclear exactly what.
go ahead and say Apple charges 130% extra for their special rubber grommets.
That's also irrelevant to the discussion. Apple is charging for a lot of things (branding for example) the article is talking about the comparative value of taking an ADM and then stripping out the drive and replacing it with a non-Apple drive. So the only vibrational difference outlined here is "the rubber grommets that hold the drive to the ADM carrier" and the reason give is that they "are chosen specifically to match each drive's vibrational characteristics"
So I asked the all important question "So what" about "if the drives vibrational characteristics are not matched" (via these special grommets)
And you made some obtuse reference to the JBOD / Dtrace clip that's been going around everywhere.
Again you have avoided a simple and incredibly direct question. All you needed was to say yes or no but you couldn't. If you state your argument clearly:
i.e. Burn-in testing is useful for most people because it would catch at least one in twenty drive failures this is based on the 6% AFR figure for one month.
Then I could get around to actually showing you why you are wrong. When you keep beating around the bush and then make (ill-informed and illogical) accusations when someone asks you what you actually need explained. It's going to be difficult showing you where you are wrong. However I expect that's what you want.
I've already stated what I believe but here it is again for the record: Apples burn-in testing does not add significantly to failure prevention compared to drives purchased over-the-counter. I expect that we are looking at something close to a failure detection rate of no better than an average risk of 1 in 300 to something worse that 1 in 500. Which is hardly a significant risk in buying a single drive for an x-serve or a set of drives for an Xraid (conflating both my example and the articles examples). Furthermore even if that is a risk, it's only a service of value to those way outside of the articles target audience.
So what is the difference between the compute and the file system nodes - no more weaseling around.
Again, I'm stuck decrypting your statements into an actual argument. So what do you want here? Personally I see little that can be definitively stated as a difference between the systems (the type of drive use could be inferred). That said there is little reason to believe that the failures shown in the first month of compute node usage are important to a *general* - This is an important word - argument which is what you appear to be making.
Wow. Nice false dichotomy.
either you are stupid, or you know you are wrong and are being evasive ...or whatever your assertion is it's wrong and I've already dismissed it and as a result you are forcing me to pick amongst wrong ideas (which there are significantly more than right ideas). ...or I've already addressed it (i.e. references to selection bias and you getting to pick and choose the data post hoc) and you don't yet understand why that is wrong.
There could be other options but all I need is one to show that your argument about me being "either X or Y" as false.
So am I to infer here that you are referring to the fact that at 1 month, the AFR reaches 6% on HPC 1's compute nodes in the first month and are implying that this says something generally about stress testing utility?
Just say if this is the case or not...and I'll explain the problem with that - no offense but considering how evasive (and illogical) you are being. I'd like to actually pin your argument down before I destroy it.
Where did I complain that Apple does burn-in testing? That's right, nowhere.
I did complain that the article asserted Apple's doing of this as valuable and beneficial and that the largest body of data does not bear out the later.
You're still being pretty evasive about what exactly you want explained.
Are you struggling to say that when you pick a portion of a dataset post-hoc it does say there's something beneficial about burn in testing?
Since you're such an expert
I'm actually not but I do take a rather quantitative approach to IT. My personal experience reflects that most people take a religious approach.
care to explain Figure 4, difference between compute nodes (left) and the file system nodes (middle) of HPC1, 1st month?
Um...you indulging in selection bias? ;-)
Seriously though. Explain in reference to what exactly?
Also, do get an engineering degree while you're at it.
Is that what you have? If so thanks for making the fight against prejudging engineers as mathematically ignorant and devoid of proper experimental methodology just that much harder.
The truth is you could have five hundred billion articles on vibration affecting (in some way) drives. However that doesn't mean:
a) That constant shouting has the same effect. For example one of my datacenters is easily loud enough that one has to shout to be heard. Are the SAN units in there constantly having higher latency. Why didn't we see a benchmark difference between inside and outside?
b) That the effect is uniform across all devices.
c) That the vibration from HD's in action is somehow comparable.
d) That this can be fixed with little rubber grommets.
e) That Apples little rubber grommets can fix them.
See the thing that you are clueless on. Is that all you have is evidence that some kinds of vibration on some systems in some environments cause some kinds of problems. However the argument you are feebly attempting to counter is that Apple's little rubber grommets actually help in some significant way.
This leaves out the most important thing. "So what" - ok if the drives vibrational characteristics are not matched what happens. Is it significant? Where is the data to say so?
In high capacity drives, vibration is a huge factor. Did you not see the youtube video of someone screaming at his drives? It got posted on slashdot.
I love statements like "huge factor" - I suspect this is what I refer to as "adjectives over evidence". Your need to use an adjective like "huge" stems from your inability to actually quantify the risk.
Yes I saw the videos. I'm wondering how much you actually thought about them though. They show someone shouting at a disk array and an increase in latency as an apparent result.
But MY statement was "Do we really need special grommets to match the drives vibrational characteristics and if so what do we lose?"
Do you not see how someone shouting at a specific disk array doesn't necessarily disprove that statement (or prove your general statement)?
In case your answer is "no". Here is a handy list of things you would need to demonstrate to get to disproving my statement from yours.
i) Constant shouting causes equal and constant impact. From the video it looks like the shouting results in an big effect on latency. However it's hard to tell how long that effect would last if the shouting was constant (this is closer to the idea of using different grommets like Apple suggests).
ii) Shouting at an x-serve (or x-raid) makes a difference. See you can't assume that one data point makes the case for all data points. This is what Sacket referred to as the disastrous inadequacy of lesser evidence. For example perhaps the Sun box is so well engineered (compared to the X-Serve) that it's one of the few that actually ALLOWS this to happen.
iii) Having specific grommets can actually make a difference. Grommets beyond a base tolerance may not make a difference. Perhaps the kind of vibration that most grommets allow is not the kind that makes a difference in latency (maybe it's about frequency, maybe it's about amplitude).
iv) Once we establish that it's possible for screws to make a difference. It still remains to be proven that APPLE's grommets make a difference. Perhaps the only kind that make a measurable difference cost $1,000,000,000 grommets and are fashioned by elves or something
v) Apples grommets make a SIGNIFICANT difference. Just because screws make a measurable difference it doesn't mean its going to be one that most sysadmins care about.
"And how long did the original drives last?"
The original drives were functioning up until we replaced the lot. The replacement was for capacity.
"you've yet to state anything of any usefulness in the comparison"
Note that this was an incidental note not a counter-argument to the idea that there is significant risk. I already addressed the alleged differences between Apple and non-apple drives in my earlier post. We did in fact add one thing to the conversation that the install was trivial and the only firmware issue was with the XRaid itself.
"there is still time for it to fail"
Clearly and even if these drives last as long as the other drives did it still wouldn't say anything meaningful (well it might cause you to doubt your idiot premise). Point being that you actually need a large sample size. Which I touch on in my earlier post.
"using cheap drives its very rarely actually worth it."
Again the largest bodies of data do not support this assertion. Enterprise drives and non-enterprise drives show little in the way of difference in terms of replacement rates. I've already posted links to the FAST study. So either there is no difference or the difference is overshadowed by other factors or this is something that only affects the very specific drives Apple is talking about.
Did you even READ the article most of the alleged differences strain credibility.
Incidentally: Our dept actually did a similar kind of upgrade on an XRAID (which was PATA but Apple had made all sort of claims: 'zero defect drives' blah, blah, blah). It's been working fine for close to a year now. The only issue was a firmware upgrade (to the XRAID) to handle the 750GB drives which would have had to be done even if we bought Apple. The cost savings was pretty significant I recall - something like 60% of the Apple price.
This was a complete replacement though. I do agree with one admins posting above though that if you are replacing a single drive then you need to be careful (and spend the money) to insure that the replacement is an exact match.