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Comment: Re:Wildly premature question (Score 1) 81

by Bruce Perens (#48620117) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

If we look at jet aircraft, wear depends on the airframe and the engines, and the airframe seems to be the number of pressurize/depressurize cycles as well as the running hours. Engines get swapped out routinely but when the airframe has enough stress it's time to retire the aircraft lest it suffer catastrophic failure. Rockets are different in scale (much greater stresses) but we can expect the failure points due to age to be those two, with the addition of one main rocket-specific failure point: cryogenic tanks.

How long each will be reliable can be established using ground-based environmental testing. Nobody has the numbers for Falcon 9R yet.

Weight vs. reusable life will become a design decision in rocket design.

Comment: Re:Traffic Furniture (Score 3, Informative) 594

by m.dillon (#48603217) Attached to: Waze Causing Anger Among LA Residents

Yes, this works extremely well in Berkeley too. There are neighborhoods on both sides of Ashby (hwy 13) and along various other routes, but the streets are relatively quiet because traffic furniture either prevents entry from Ashby or directs the flow such that there's no point using them for the commute. And they don't inconvenience the residents either. For a resident or for local travel, entering and exiting only adds a few seconds. For a commuter, trying to use residential streets just doesn't work.

The barriers seem to be favored over speed bumps. Over the years the speed bumps have been made softer (15 mph bumps now instead of 5 or 10 mph bumps), and are generally concentrated only in areas that simply cannot be blocked off for fire and other safety reasons.


Comment: eh I don't know (Score 1) 186

by nomadic (#48563743) Attached to: NetHack: Still One of the Greatest Games Ever Written
I don't know about NetHack. I started with Hack back in the late 80's, and have played that then NetHack off and on since, usually picking it up for a day to a few weeks then losing interest. Never finished the game. I'd usually play until I got a guy down pretty far with a great kit, then when he inevitably died from something stupid, I'd be annoyed and lose interest again.

It's a good game, maybe even a great game, but it's not a perfect game and it's not the best game ever. Too much of it is just not fun. The major design flaws in my mind:

* Once you hit the labyrinths and have to deal with the wizard following you around, it just becomes a grind. A little bit of a grind in order to achieve something afterwards is fine but when a game becomes work then that is not.
* It doesn't give you a fair way to figure out what to do. A lot of the actions required to finish the game are neither hinted at nor intuitive.
* It's too repetitive. It doesn't exercise my mind much; you just do the same things again and again.
* It's too time-consuming, and frequently unnecessarily so (which goes back to the repetitive point).

Anyway, just my thoughts.

Comment: Re:lowering price? (Score 1) 127

by m.dillon (#48549345) Attached to: Samsung SSD 850 EVO 32-Layer 3D V-NAND-Based SSD Tested

No, actually for flash it does NOT have to be extremely good. Flash memory production can handle lots of bad bits due to process errors. The controller firmware will simply map-out the bad bits, simple as that. If 1% of the flash cells are lost due to process errors, it just isn't a problem.

The same cannot be said for cpu and ram logic.


Comment: Re:You can pry my wallet from my... (Score 0) 375

by m.dillon (#48502349) Attached to: The Cashless Society? It's Already Coming

Hey mythosaz... I think you will find that trying to save every single one of the many billions of people in the world from all the nasty carrots which get wiggled in front of their faces by big companies every day is a losing proposition. You'll just burn yourself out without making any impact. My recommendation... worry a bit more about yourself and a bit less about everyone else.

Plenty of people can handle a credit card no-problem. Plenty of people cannot. And the same could be said for a thousand other little bits and pieces of life. That's just the way the world works.


Comment: Re:What's happening to Linux? (Score 1) 257

by Sun (#48486191) Attached to: Bad Lockup Bug Plagues Linux

Funny, I'm moving in the opposite direction, but reach the same conclusion. Working with (most) modern IDEs just seem like masochism after you've used VIM.

The learning curve for vim is horrible. I can understand anyone who gives up before reaching reasonable productivity levels. Once you've gone through it, however, the IDEs are just no competition.


Comment: Re:It DOES have permission (Score 4, Insightful) 234

by m.dillon (#48475327) Attached to: Uber's Android App Caught Reporting Data Back Without Permission

No, in fact the vast majority of people who run an IOS app on an Apple device who see a permission request pop up that they don't like, say 'No', and the app continues to run just fine.

Even better, the apps on IOS tend not to request absurd permissions in the first place because they know those pop-ups will annoy their customers enough to either say 'no' anyway or not use the app in the first place. Its a black blotch for an IOS app to request permissions that it does not need, and Apple customers call them on it in the reviews.

Whereas with android, everything is quiet and silent and people run apps without really understanding what data they are giving away, EVEN if they have read the manifest... so app writers can get away with almost anything and consumer privacy on android is poorer for it.


Comment: Re:Have you ever used Android? (Score 1) 234

by m.dillon (#48475289) Attached to: Uber's Android App Caught Reporting Data Back Without Permission

Google changed the way the permissions are described in order to combine non-invasive permissions and invasive permissions under the same label. Even a person reading the permissions off doesn't really have a clue about how much access the app actually has to their data.

In anycase, this is why I stopped using Android phones and went with iOS. Apps can't play these sorts of games on iOS.


Comment: Re:MO as an HDD (Score 1) 215

by m.dillon (#48475245) Attached to: Consortium Roadmap Shows 100TB Hard Drives Possible By 2025

Jeeze, I remember those. Hey, how about the Bernoulli box? I had one of those too. Might not be M.O. though. Think it was just magnetic.

There is one basic problem with megneto-optical drives and why they've basically fallen off the edge of the earth... instead of having to have one high-precision/high-bw part in the drive you now have to have two. In the world of storage, that makes it too costly a technology to produce.


Comment: Re:So that means we're still gonna be buying (Score 1) 215

by m.dillon (#48475179) Attached to: Consortium Roadmap Shows 100TB Hard Drives Possible By 2025

Every personal laptop/desktop/server box has a SSD which holds the machine base (boot, swap, root, home dirs, etc). For laptops and workstations, the SSD also holds nominal data and there is no HDD at all. On the servers, the SSD is beefier and also caches the HDD.

Bulk data is stored on a large 2TB HDD on the server and exported via NFS and samba. There's another 2TB spare on the server.

There is a backup machine on the LAN in another part of the house with a 2TB HDD and there is an off-site backup machine in a colo with two 2TB HDDs (in addition to the normal SSD as described above). Both have around 60 days worth of incremental backups of everything.

I gave up using RAID of any sort for personal data long ago. It just makes things *less* dependable and unnecessarily expensive in heat and power. Not even needed for speed since the SSD will cache ~200GB worth of HDD data.

Right now my personal data (the permanent data that I back up) clocks in at around 1TB. 90% of it is pictures and videos (DSLRs generate a godawful amount of data, the RAWs are 20-40MB each).

I don't download videos or music. No point any more when it can all be streamed. I don't know anyone who bothers storing 3rd party video any more. However, I have friends who were CD junkies before CDs died away and do maintain large music libraries. I also know a few people who run torrents and sometimes dedicate a TB or two to that, but certainly there is no reason to back up something like a torrent let alone waste a RAID on it. I don't see the point myself, it's just a huge waste of power and bandwidth.

For the DragonFlyBSD project we run a 12-blade server in the colo, each with four 2.5" drives. One or two SSDs (boot + swap + hddcache + home dirs on most of the blades), and 1-3 HDDs for temporary bulk data which we don't bother backing up. e.g. build boxes. With a few spare blades in case something fails. SSDs hold anything important, except for the developer blade but now that I look at it, the 'backed up' portion of peoples home dirs on the developer box only clocks in at 83G so that could go onto the SSD as well. The working storage that isn't backed up is currently running ~400G or so of used space, mostly crash dumps and copies of build trees and such. Everything that we care about is backed up locally and remotely but again it only amounts to a ~1TB or so. Most of the bulk data on the blades, like copies of numerous source repos, is generated and does not need to be backed up.


Mediocrity finds safety in standardization. -- Frederick Crane