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Comment: Re:Check their work or check the summary? (Score 4, Informative) 473

by OverlordQ (#49338341) Attached to: No, It's Not Always Quicker To Do Things In Memory


It is easy to explain the results: In high-level languages such as Java and Python, a seemingly benign
statement such as concatString += addString may actually involve executing many extra cycles behind
the scenes. To concatenate two strings in a language such as C, if there is not enough space to expand
the concatString to the size it needs to be to hold the additional bytes from addString, then the
developer has to explicitly allocate new space with enough storage for the sum of the sizes of the two
strings and copy concatString to the new location, and then finally perform the concatenation. In Java
and Python strings are immutable, and any assignment will result in the creation of a new object and
possibly copy operations, hence the overhead of the string operations. The disk-only code, although
apparently writing to the disk excessively, is only triggering an actual write when operating system
buffers are full. In other words, the operating system already lessons disk access times. A developer
familiar with the language and system internals readily notices the causes of this observed behaviour,
but this behaviour may be easily missed, as indicated by examining similar cases in production code.

Comment: Re:This is the dumbest research I've seen this yea (Score 1) 473

by MerlynEmrys67 (#49337175) Attached to: No, It's Not Always Quicker To Do Things In Memory
What do you expect... There is only one person that MIGHT have a computer background on the paper... This is pure academic fluff, compare an in-memory database with a spinning rust based database and see how many operations you can get out of each one performing the same operation.

Comment: Re:Check their work or check the summary? (Score 1) 473

by MerlynEmrys67 (#49337151) Attached to: No, It's Not Always Quicker To Do Things In Memory
Here is how you make the results faster.

1) Calculating 1MB of data and writing it to disk
2) Calulating 100K of data, writing it to disk, repeat 10 times.

If the time to write to disk is what takes most of the time, then getting the operation started early and writing to disk in parallel to calculating your data will always win. In their case - what they have done is made the in memory operation exceedingly stupid so it takes too much time. I could trivially write C code that blows their operation out of the water, unfortunately - their Java/Python code are hiding a LOT of inefficiencies in the in-memory operation. So compare their disk operation, with a cache line optimized in-memory calculation and a disk cache optimized disk write operation... It won't even be close.

Comment: Re:Running only Windows on a Mac (Score 1) 207

by slaker (#49313319) Attached to: For Boot Camp Users, New Macs Require Windows 8 Or Newer

I have a "Type"-style (the same sort the Pro 3 uses) purple cover for my Pro 2. I paid $58 for it on Amazon. I actually wanted purple but I could've gotten a pink one even cheaper. Would I take a refurbished keyboard? No question that I would. We use other people's keyboards all the damned time, especially those of us who have an IT support component to our jobs (or for that matter anyone who has ever used an ATM). Am I looking places besides major retailers? No I am not. If you can't find one at a significant discount, you probably shouldn't be buying anything over the internet.

The Surface keyboard is entirely optional. I don't completely love the Windows on-screen keyboard, though it's a damned-sight better than the one Apple ships with iOS (Apple is either not a big fan of basic literacy or thinks letters should always be displayed in uppercase regardless of the state of the shift key). In practice I've found that I don't use it much because my Surface Pro more as a very capable mobile device than as something for real work, but I have powerful desktops and a good laptop available to me as well.

Speaking to the quality of Apple's input devices specifically, I find the lack of key travel and mildly idiosyncratic layout on Apple's own branded keyboards uncomfortable for serious typing in exactly the same way the Surface Type-style keyboard is. I also question the ergonomics of the palmrests on its notebooks and the insistence on comically oversized touchpads as input devices. I wouldn't exactly say either option is without compromise.

Comment: Re:Running only Windows on a Mac (Score 2) 207

by slaker (#49311865) Attached to: For Boot Camp Users, New Macs Require Windows 8 Or Newer

MSRP is $130 for a Surface Pro 3 keyboard. They generally sell for under $100, sometimes under $80 if you don't mind one of the less popular colors or getting a refurbished one. I'm not sure where you're getting this $200 figure from, but it's significantly off-base.
Further, the Surface Pro doesn't have a hard requirement that you use Microsoft's keyboard. You can use any bluetooth or USB input devices you'd like.

Comment: Re:the establishment really does not like competit (Score 4, Informative) 366

by rsmith-mac (#49289575) Attached to: Uber Shut Down In Multiple Countries Following Raids

This doesn't mean there are no regulations - it means that Uber drivers are required to pay for the cost of a background check by the police department, and provide proof of insurance. This cost is tiny in comparison to buying a medallion, and provides the same level of safety as the background checks the taxi companies were running.

Keep in mind however that only a handful of cities use Medallions. Outside of NYC and those other cities, Uber is getting busted for exactly what you propose: they refuse to do things like pay for police background checks and require drivers to hold a commercial driver's license. Uber is managing to break the law even in cities with a limited number of common sense laws.

Comment: Re:AKA as Database Syndrome (Score 2) 111

by rsmith-mac (#49263121) Attached to: Scientific Study Finds There Are Too Many Scientific Studies

The crop of PhDs from the last 10 or so years are either unable or unwilling to 'hit the books'. If they can't find it in an electronic database AND easily download a PDF, they will ignore the existence of the work.

One of the primary reasons we even have computers is to help organize and locate information. Meanwhile, because computers are so good at it and we now have so much information to process, information that is not available to a computer in 2015 is not useful information.

To communicate is the beginning of understanding. -- AT&T