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SSD-HDD Price Gap Won't Go Away Anytime Soon

Calinous Re:RAID? (248 comments)

You might try next time to use CloneZilla. I've used it to "copy" from and to partitions of different sizes.

yesterday
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SSD-HDD Price Gap Won't Go Away Anytime Soon

Calinous Re:Multiple heads? (248 comments)

Actually, "client" workloads (personal computers) aren't very parallel so the requests are served sequentially. As such, this won't help too much.
      Even now, hard drive performance (if computed separately for client-workloads and server-workloads) uses queue length 1 for client and queue length 32 for server.
      By the way, if I remember correctly multiple requests on flight were implemented on SATA standard for client drives, 10 years ago or so on (SCSI had them for quite a while). I'm not sure Windows XP uses these queues.

2 days ago
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SSD-HDD Price Gap Won't Go Away Anytime Soon

Calinous Re:There are other techs waiting in doorway... (248 comments)

10 times ago I heard about IBM and others working on new technologies to replace memory. Holographic cubes, MRAM, ... Are they still 10 years away?

2 days ago
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SSD-HDD Price Gap Won't Go Away Anytime Soon

Calinous Re:RAID? (248 comments)

Seek time is the time for r/w head movement (closer or farther from the disk center) PLUS the wait time until the wanted data is rotated under the read/write head. So, unless you go with r/w heads for each sector on the hard drive, you can't reduce part of the seek time. And you could rotate the disks faster (like in SCSI 15k rpm disks), but there's a limit there too.
      Will HDDs ever be performance-competitive at the same cost to SSDs? At the current technology level, no. Will SSDs ever be price-competitive at the same capacity? Hardly, considering adding another platter and r/w head to a hard drive is a quite inexpensive way to increase capacity, while adding another set of flash memory chips is an expensive way to increase capacity.

(oh, and a read/write head for each data strip was used in the 50s and 60s - see magnetic drum memory).

2 days ago
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NASA To Send SpaceX Resupply Capsule To ISS Despite Technical Problems

Calinous Re:wanted to recover (71 comments)

They must have extra fuel due to the "launch with only 8 out of 9 engines working" - when flying with 8 engines, they need more fuel to accelerate as they have lower impulse. Also, the engines' output might vary somewhat, so they most certainly have excess fuel. I'm not sure if all this excess fuel is enough for a successful landing or they might need more...

4 days ago
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The Highest-Flying Wind Turbine

Calinous Re:hm... (143 comments)

This electrical cable can function as a tether. Maybe a steel cored, twisted aluminium strands cable (as used in medium and voltage transmission) would offer both low electric resistance, high strength, high reliability, ...
(P.S. I have small lengths of that kind of cable at home. It's probably overkill for a 10-houses sized balloon, but it can be built in smaller gauges)

about three weeks ago
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Taxis By Algorithm: Streamlining City Transport With Graph Theory

Calinous Re:The "level playing field" taxi companies demand (72 comments)

This can reduce waiting times in "taxi rush hour" - would you prefer to wait 15 minutes for "your own" taxi, or share one that comes in 5 minute?
Also, if the cab carries two different passengers, cab drivers get payment from each.
      In Athens, Greece, the cabs that carry one passenger might stop and take another one that goes in the same direction (and get full payment from one passenger and partial or full payment from the other). It helps a lot with the "I can't find a cab at this time" problem.

about three weeks ago
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Intel Announced 8-Core CPUs And Iris Pro Graphics for Desktop Chips

Calinous Re:First hand knowledge (173 comments)

There was a time (Prescott Pentium 4, or maybe all the Pentium 4 processors) when the ALU was "double pumped" - it worked at twice the frequency of the rest of the system. So, it was on "half a general CPU cycle" or a "full cycle of the ALU).
      But that was quite a long time ago, and more than 3 microprocessor generations had passed.

about a month ago
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EU Project Aims To Switch Data Centers To Second Hand Car Batteries

Calinous Re: Great (87 comments)

This is for Li-Ion or similar batteries used in hybrids (and maybe full-electric cars), not for the lead-acid (which usually are discarded when they have very little usable charge)

about a month ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

Calinous Re:Still a ways to go (131 comments)

A supertanker has a deck about 300 by 30 meters, so 10,000 square meters. With an optimistic 100W from square meter, and 8 hours a day of full power, you'd get about 8 MWh (or some of 28,800 MJ) of energy a day. At 43 MJ/kg for diesel fuel, that's the equivalent to some 700 kg of diesel fuel a day.
      Now, ships use heavy fuel oil when outside territorial waters (which is much cheaper), so a full deck of solar panels wouldn't save you very much money. And those panels would be exposed to salt water, storms and so on.
      I haven't found the "common" power generation for ultra large crude carriers (oil tankers), but max power seems to be over 80MW - assuming they're going at a quarter of maximum power, the solar cells would give you at most 1/60 of the needed power per day.

about a month and a half ago
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I'd prefer military fiction books that are ...

Calinous Re:Not at all (236 comments)

Even now, some people can temporarily (or completely) lose their right to vote or be elected (medical reasons or for - by example - corruption while being a member of Parliament).

about 2 months ago
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Elon Musk Says Larger Batteries Might Be On the Way

Calinous Re:Dead end (191 comments)

I drive an Opel Astra (two doors) with a 54 liters fuel tank. I used to drive a '92 Passat (reviewed as a compact on US sites) which had a 70l fuel tank.

about 2 months ago
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How To Hack Subway Fares Using Fare Arbitrage

Calinous Re:They shall not pass! (240 comments)

Not to mention parking spaces, which usually are at a premium in cities

about 2 months ago
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How To Hack Subway Fares Using Fare Arbitrage

Calinous Re:How stupid (240 comments)

Public transit systems are (usually) heavily subsidized. I remember the city of Tallinn (I think) introduced free public transportation, as the city did pay 75% of the real cost of the tickets anyway.

about 2 months ago
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DDoS Larger Than the Spamhaus Attack Strikes US and Europe

Calinous Re:And yet... (158 comments)

Home internet at 50 Mbps means 50 Mbps downlink and almost certainly less than 10 Mbps uplink (probably less than 5 Mbps) - and uplink is what matters in this case.

about 2 months ago
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Atlanta Gambled With Winter Storm and Lost

Calinous Re:Pffft (723 comments)

If the roads are sanded, winter tires will grip sand grains in the small creases/cuts, and this will help even on ice. Lacking sand, only chains (in they break the ice under them) and studded tires help.

about 3 months ago

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