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Comment: Re:This is the dumbest research I've seen this yea (Score 1) 486

by falzer (#49338487) Attached to: No, It's Not Always Quicker To Do Things In Memory

>According TFA, they actually do an explicit sync to disk at the end of the writes. So it's not purely writing into cache.

The code in the paper says they flush before closing the file. This is not the same as a sync. They don't even flush (or sync) after each write.

Comment: Re:This is the dumbest research I've seen this yea (Score 1) 486

by falzer (#49337119) Attached to: No, It's Not Always Quicker To Do Things In Memory

>This is the dumbest research I've seen in 2015. There was actually no computation involved -- they just wanted to write a long string to disk. They concluded that adding the superfluous step of concatenating strings in memory, then writing to disk, was slower. Well duh! That's not what memory is for!

Agreed with you on the uselessness of their research, but that is most definitely one important and common use of memory: buffer caches used by the operating system.

Effectively, they unintentionally tested the speed of the OS to concatenate strings vs Java or Python. The researchers are wrong right out of the gate: they say "Heavy Disk Usage" in their research headline, but at no point did they actually test disk performance, everything they did is being handled by the OS buffer cache.

All the researchers have shown is that string concatenation operations in Java and Python are atrociously slow. The java example used the naive form a=a+b; to concatenate strings, which is one of the slowest ways to do it in Java if you are doing repeated concatenations to a string.

If, in their tests, they had also done a string concatenation in C by allocating a buffer and appending to it using a pointer (not strcat) the speed difference doing that vs. 1 million write calls would have been negligible.

Also, if they sync'd after each of a million 1-byte writes to test how slow "Heavy Disk Usage" is compared to a single write of a million bytes, they wouldn't have bothered finishing this paper at all because it's so damn obvious that memory is faster.

Comment: Re:I don't get it... (Score 3, Insightful) 98

by anethema (#48383921) Attached to: US Gov't Issues Alert About iOS "Masque Attack" Threat

Let's also keep in mind that apple apps ONLY run in a sandbox, and this virus does not break out of it. The worst the app can do is be installed if you don't actually go into it and do stuff.

The main danger is that the app could masquarade as a legit app like browser/banking etc and maybe trick you into using it.

But the sheer number of steps needed to install it, then almost crazy foolishly using it afterwards, it isn't much of a threat.

Comment: Re:They didn't TEST anything... (Score 1) 986

Have you read this? http://arxiv.org/ftp/arxiv/pap...

Having glanced over the original stuff, and reading through this, as a non scientist it seems pretty convincing that the 'independent' test is missing a ton of data that would support any of their conclusions.

Comment: Re:Help for women with no sex drive? (Score 5, Informative) 216

by anethema (#48128237) Attached to: Oxytocin Regulates Sociosexual Behavior In Female Mice

There are several -Genuine- treatments (read: Aphrodisiacs) in trials right now.

The main promising one right now is PT-141 (Bremelanotide)

The main downside is it must be injected which will skeeve a lot of women out. It does work on men AND women though.

From their site: " In a recently completed Phase 2B clinical trial, bremelanotide 1.25 mg and 1.75 mg doses significantly increased sexual arousal, sexual desire and the number of sexually satisfying events, and decreased associated distress in premenopausal women with FSD. Efficacy was seen in both women with hypoactive sexual desire disorder (HSDD) and combined HSDD/female sexual arousal disorder (FSAD)."

Since it is currently just in trails and unscheduled, you can order it right now from research peptide sites.

Let's say a friend's wife has tried it, and she was as horny as a 18 year old boy for about 2-3 days. It is genuine arousal, not some blood flow modifier etc like Viagra.

Comment: Re: Low write endurance? (Score 1) 64

by anethema (#47709123) Attached to: AMD Launches Radeon R7 Series Solid State Drives With OCZ

Sorry wrote it wrong but had it right in my calcs. I meant 30gb/day for 4 years.

It is 30 GB / day for 4 years which works out to 43 TB. Hopefully that makes it a bit more clear.

The point isn't that you may or may not use that much, its that their talking point is high endurance, and it actually has very low endurance compared to other consumer SSD lines.

Comment: Low write endurance? (Score 4, Insightful) 64

by anethema (#47704057) Attached to: AMD Launches Radeon R7 Series Solid State Drives With OCZ

Their claim is they are focusing on reliability and write endurance but it looks like they have some of the lowest endurance in the industry.

Even the drive it is supposed to be a bit of a clone from is rated much higher.

AMD R7: 4GB for 4 years = 43TB (Odd that they don't say this is dependent on drive size, which it would be.
OCZ Vector 150: 50GB for 5 years = 91 TB (Also not scaled for drive size)
Samsung 840: 1000 cycles. In their smallest drive this would be around 120 TB. Samsung is using lower endurance TLC here so this is even more odd.
Intel 730: 70TB over their 5 year warranty is 127 TB Highest of them all for MLC.

Now in real life, the AMD and OCZ drives may go much further before they fail, but you have to go off of their ratings for comparisons or all hell breaks loose (Tests have shown the Samsung drives lasting over 3000 cycles before beginning to reallocate sectors). Especially for the larger drives (A 240GB drive should have double the write endurance of a 120GB drive).

So yeah I find it odd that endurance is one of their talking points when they have by far the lowest endurance of any of the common drives out there, including the supposedly very similar Vector 150.

Comment: Re:all I'd need there is a sports iPod (Score 1) 427

by anethema (#47323967) Attached to: Ask Slashdot: What Would It Take For You To Buy a Smartwatch?

Ya my current watch (Casio pathfinder http://i219.photobucket.com/al... ) is already pretty smart as far as watches go (has altimiter, barometer, compass) and half the face is a solar panel. I've not had to change a battery since I got it, and expect I wont for a long long long time.

Be nice if a smart watch could be rugged without being the size of a phone, and have solar or some kind of decent battery life. A month even would be nice.

"They that can give up essential liberty to obtain a little temporary saftey deserve neither liberty not saftey." -- Benjamin Franklin, 1759

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