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Multi-Threaded SSH/SCP
neo writes "Chris Rapier has presented a paper describing how to dramatically increase the speed of SCP networks. It appears that because SCP relies on a single thread in SSH, the crypto can sometimes be the bottleneck instead of the wire speed. Their new implementation (HPN-SSH) takes advantage of multi-threaded capable systems dramatically increasing the speed of securely copying files. They are currently looking for potential users with very high bandwidth to test the upper limits of the system."
I get a lot of use out of ssh for moving files around and rsync is definitely the best way to do heavy lifting in this area. Improving scp would be good to. I can't wait to hear what Theo thinks about this. I don't see him as a fan of adding complexity to improve performance.
Big scp copies through my wifi router used to cause kernel panics under netbsd current of about a year ago. I never had that problem running rsync inside ssh.
http://michaelsmith.id.au
Makes you wonder how many innovations can either be directly attributed to or partially attributed to the distribution of porn (not (necessarily) that this is).
VHS v Betamax comes to mind.
I really hope this will make it into OpenSSH after some security auditing. The performance gains was pretty impressive. It will make ssh much more fun for rsync, backups and other times when i transfer large files. I also wonder if one cant get similar performance gains with normal ssh and for example forwarded X-windows. That would be very interesting indeed.
HTTP/1.1 400
I think this story is interesting because it shows a general trend: increased focus on multi-threading. We will see much more of this in the future as multi-core and multi-processor systems become more common. This trend is driven not by porn though, but by that other big driving force behind the computer industry, gaming.
People are always willing to pay more to be entertained that to be educated.
Which explains why football players and movie stars will get paid more than the innovators that carried out the research to develop the broadcast technology that helped to make those stars famous.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
I won't lie to you -- being a parent is no laughing matter. It is a ton of work. It can be amazingly stressful and expensive. I've been through periods that I look back on now and wonder how the hell I managed to pull through without going completely insane. But if you ask me, the rewards outweigh the difficulties ten to one.
When your child first looks up at your face and you see actual recognition in her eyes... when you see all the blocks fall into place as she figures out how to do something for the first time... look, I know it sounds really sappy and smarmy, but seriously (srsly) it is absolutely indescribable. This thing started out as a bit of genetic code from two people, and now it is actually self-aware and sentient. How cool is that? What geek can't be astonished at these emergent properties, derived from a program more complicated than you can possibly imagine -- a program that has spontaneously evolved over time?
And you get to see her mental map evolve. You watch branches get added to her decision tree. You observe as she learns how to acquire information, process it, and decide how to act upon it. And all the while, you mold her view of the world based on your interactions with her. I don't know about you, but I find that not only fascinating, but incredibly rewarding.
Before my daughter was born, I was terrified too, and somebody had said these things to me, I would've said, "Yeah, okay, I'm sure it's great and all, but I'm sure you're exaggerating somewhat." That's because there is something that happens to you when it's your kid. There's some very ancient, very basic code that gets turned on in your brain that says "this life is your responsibility, and you must do everything you can to ensure its safety, survival, and growth". I can't explain it because I honestly believe it's something buried deep beneath the conscious mind.
Whatever the case, if you honestly don't want the baby, for it's sake, put it up for adoption. Don't make it live a life with a father who doesn't care for it. I'm being absolutely serious here. Find a loving couple who are unable to have kids of their own.
(Posting AC because this is way offtopic, and because there are a lot of single, selfish, bitter child-haters out there with mod points to burn... but I had to say something.)
Actually, this is one of the main reasons why we did this. If you look at where processor architectures are going they aren't necessarily increasing the pure computational power of each core as much as they are using more and more cores. If you are in a situation where you have a single threaded process that is CPU bound - like SSH can be - you'll find that throughput rates (assuming that you aren't network bound) will remain flat. In order to make full use of the available network capacity we'll have to start doing things like this. There is still a lot of work to be done but we're pleased by our progress so far.