Actually, launching a rocket into the sun is extraordinarily difficult, and I think is still beyond our abilities (please, some of you rocket-scientist types out there correct me if I'm wrong....)
The problem is, we're orbiting the sun, and so is anything we launch. Earth's orbital velocity is pretty high (29.8 km/sec according to this).
Any rocket that hit the sun would have to first kill its initial orbital velocity of 30km/sec, or it would "miss" the sun and whip around the sun in a comet-like orbit.
I was wondering when someone who knew what they were talking about would come along. I have never seen so many highly-modded posts (even on/. - honest) by people who haven't got a clue what they are talking about.
If only I had some moderator points, I'd be modding DOWN all the posts here that are complete bullshit.
Moderators, please don't just mod someone up because they *sound* authentic.
Re:I've been playing infinite games for years.
on
Infinite Games?
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· Score: 1
The problem is Frontier and First Encounters (Elite 2 and 3) are DOS only... go to http://www.jaj22.demon.co.uk/ to download a hacked version of Frontier - binaries for Win32 and Linux are available.
If you've got an interest in astronomy, check it out - Travel through realistic solar systems, explore, and complete missions. The game is very open ended, and although it predates 3d acceleration, the techniques it uses to render fractal planet surfaces has never been used elsewhere (as far as I know) and still works well.
Actually, Peter Jackson *has* arranged for the special edition to be shown in the Embassy theatre, here in Wellington, New Zealand where the film was made... But only once, the night before the special edition DVD is released.
The Embassy theatre is a kick-ass old theatre that has been refurbished recently. Its got an amazing sound system and what I was once told is the biggest screen in the southern hemisphere. It used to have nearly 1800 seats!!! Apparently Peter wanted the world premier of FOTR to be held here, but New Line Cinemas said no (they wanted it somewhere on the map, like, say, London...) but agreed to let Peter show the special edition here instead. Some info about the embassy theatre can be found here
I had an opportunity to get tickets for the screening, but I decided against it - we're talking about FOUR hours of sitting on your arse without moving, once you include the previews etc. Maybe if they had an intermission...
Also, apparently Peter doesn't like the term 'Directors cut' because he always intended to make two versions, the full version and a shorter version for the box-office.
.Net/Java performance?
on
Itanium Problems
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· Score: 2, Interesting
Hey regarding compilers.... Does anyone have any info about how.NET will go on Itamium, or even Java?
Think about it,.Net and Java are all about JIT compiliation of some intermediate bytecode to native machine code as needed.
Itanium is all about moving the complexity of moving out-of order execution and stuff onto the compiler at compile-time instead of doing it at runtime with silicon.
Doesn't this imply that JIT compilation of Java Bytecode or.Net assemblies at runtime will have a higher performance overhead on Itamium, if the JIT compiler wants to extract the best performance out of the chip?
Has anyone here seen/done any benchmarks for this?
A clever VM system is more important than ever, when you combine it with an effective disk cache.
Yes, Ram is cheaper and faster than ever, but stopping your OS from using a swap file/partition is gonna stop your OS from efficiently using your ram.
Your machine should be allocating as much memory as possibe to a disk cache, even if this reduces the available memory to the extent that active processes start paging, because the swap file paging is optimised by the disk cache too.
It is usually better to swap out pages and keep your cache large than to keep rarely used pages in memory at the expense of cache, because even if you need those pages they will quite likely be in the cache.
Even if you have a shedload of memory (especially so!) you will get better use of your memory if you use some of it as a disk cache than if you don't page rarely-used pages to disk.
I dissagree, I think MS deserves MUCH more than they get. They are primarily a marketing company, and yes, they make some good things, but they always try their hardest to lock you in once you bite - classic carrot-on-a-stick technique - they INVENTED embrace and extend.
I think the poor security record of products like NT/2k is *very* dissapointing, when you consider they COULD have been such good products. NT's security is pretty comprehensive and well thought out, and leaves linux in the dust for features, but they missed the last hurdle - e.g. out of the box installs of NT and 2K give FULL file permissions to ALL the system files to everyone by default, and even worse, all of the system daemons (IIS etc) run in the security context of local admin! (localsystem). That way, something as simple as a buffer overflow in IIS can give you local root access. There is no need, yet I've never managed to get the IIS service to run as anything other than localsystem (and I can't find any docos relating to this at MS either - anyone help?)
I think something that both Microsoft and the OEM's count on is the time it takes from the time a bug is found until the time the bug is exploited! In the case of Code Red and Nimda I think that time spanned months.
No, in code red's case the discoverer of the bug didn't go public until the patch was out, so the delay was effectively zero. Nimda used up to 7 different holes, but these were also patched very quickly.
It was months until the actual automated exploits and worms started appearing to exploit these well known holes, there was no excuse for being caught by Code Red or Nimda.
If there is one thing you can't accuse microsoft, its not being prompt to release patches for their holes... its just that their patches are requred far to frequently...
I can't find any info on MS's site right now, but I'm sure that OEMs that supply W2k datacenter are required to have a support team ONSITE at MS's campus 24/7.
This article raises a very good point, but Microsoft's idea behind datacenter was they hat total control over the hardware environment, and they made sure OEMs would stand behind it too, so I'd be very surprised (and dissapointed) if the OEM didn't contact their customers *immediately* with patches whenever there was a hole (and I'd guess they are pretty busy too;)
... He's got a real pair of clangers for doing this and releasing it! I really hope he stays anonymous.
He's done a very thourough job of reverse-engineering too. Read his README file, very interesting... some quotes:
"One very important effect of this scheme is that Microsoft fully controls who gets to write modules that interact with the basic Microsoft media modules. Without a certified public key (and the corresponding private key) it is impossible to write a compatible DLL that interfaces with their code. Since Microsoft controls the issuing of certified public keys, they also have complete control over who is allowed to make compatible and competing products. Microsoft's reputation for being generous to competitors is well-known, so this effectively gives Microsoft a technically guaranteed monopoly power."
And his 'Messages' at the bottom:
"Microsoft: You guys have put together a pretty good piece of software. Really. The only real technical flaw is that licenses can't be examined for their restrictions once they are obtained. My real beef is with the media publishers' use of this software, not the technology itself. However, it's easy to see where software bloat and inefficiency comes from when this code is examined: every main DLL has a separate copy of the elliptic curve and other basic crypto routines, and parameters passed back and forth between modules are encrypted giving unnecessary overhead, not to mention all the checks of the code integrity, checks for a debugger running, code encryption and decryption. Perhaps you felt this was necessary for the "security through obscurity" aspect, but I've got to tell you that this really doesn't make a bit of difference. Make lean and mean code, because the obscurity doesn't work as well as you think it does.
Justice Department: Maybe this should really be addressed to the state officials, since it looks like the current U.S. administration doesn't care too much about monopoly powers being abused. But for whoever is interested, there is a very serious anti-competitive measure in this software. In particular, for various modules of the software to be used, you must supply a certified public key for communication. Guess who controls the certification of public keys? Microsoft. So if someone wants to make a competing product, which integrates well with the Windows OS, you will need to get Microsoft's permission and obtain a certificate from them. I don't know what their policy is on this, so don't know if this power will be abused or not. However, it has the potential for being a weapon Microsoft can use to knock out any competition to their products."
The main reason Win9x is so crap at multi-tasking is most of the kernel isn't re-entrant, even though it is pre-emptable, 'cause of all the ugly 16-bit code in there.
Thats why if one process in win9x locks up, quite often everything else gradually locks up too, as other processes can't get to the kernel until the original process unblocks.
Win9x "multi-tasking" is such an ugly kludge it shouldn't really be called that at all.
The overall poor stability of Win9x is more to do with unprotected memory than multi-tasking cockups tho.
Windows 2000 can change favor from background to foreground processes on the fly (right click 'My Computer' and check out the properties)
That doesn't change NT's pre-emption behavior dude. NT automatically boosts the priority of the process that owns the topmost window, to make the UI Snappier... that option just turns this on or off.
NT/2K also uses varying process quantums depending on if you are using it as a server or workstation, but I don't think the favour background/foreground processes option tunes this... I'm pretty sure the quantum length is the only (major) difference between NT server/workstation or W2K pro/server. Longer quantum = lower context-switching overhead = more throughput.
On NT you can't kill a process when it is in the kernel/device driver either... I get that a lot when I put a bad CD in my drive and try and read it. The app hangs, and I try and kill it only to be told "this task cannot be ended at this time".
Yeah, you can start a process as another user, but still in your regular session (like NT and 2k) or, new to XP, you can start another session as a different user, on a different desktop while the 1st user is still logged on (with programs running and all)
This, and the cleartype support are about the only things I think XP has got going for it. I'm gonna stick with 2k unless MS releases a method of un-installing all the crap that is built in - Firewall, messenger, moviemaker etc etc etc.
Ohhh.... that sounds like a troll, but I just can't resist biting...
My MacOS 7, 8, or 9 machine has a much more responsive interface on a 75-MHz machine than Gnome on a 500-MHz Linux box
Uhh.. and thats with WHAT apps running concurrently? You gotta remember, GNOME is quite a bit more complicated than MacOS, and GNOME is working through a shedload more layers of abstraction (X, display drivers etc...) In MacOS<10 (or Win3.1) if a misbehaving app wanted to hog the CPU, then the interface just doesn't respond. The whole point of pre-emptive multitasking is that if the app doesn't play nice, you still can do other things.
Anyway, the your whole point is kinda... pointless, as apps running on a pre-emptive OS still are probably yeilding the CPU voluntarily if the system is under a light load. It isn't until things start really working, or until an app starts hogging CPU that it is pre-emptively sheduled out against its wishes.
a batch process started up on my UltraSPARC today that rendered the box unusable...
quite possible, if it had a high priority. At least you have the option of changing priorities, on a non-preemptive OS there is no concept of priorities, each app can hog as much CPU as it likes!
But I guess you're happy using MacOS 7-9 instead of MacOS X, or Win3.1 instead of Win9x.
Win9x barely qualifies as a pre-emptive OS tho, most of the kernel is single-threaded, so apps tend to block each other too much - try NT4/W2k.
Basically, in 1993 someone looked closer at mars's orbit, and found its axial tilt isn't constant, but varies from 0-60 deg, over a period of 157,000 years!
Needless to say, an axial tilt of 60 degrees is going to royally screw up the climate. Turns out the moon is stabilizing earth's orbit, our axial tilt varies 2.5 degrees every 41,000 years. It has been calculated that without the moon, we would wobble between 0 and 85 deg tilt... lucky eh?
According to the article, Earth is actually at the inner edge of the habitable zone, and the only reason mars is so cold is it is too small to hold an insulating atmosphere.
Re:Did anyone read this article and not get the ur
on
Son of HAL For Sale
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· Score: 1
"verging on artificial intelligence"
Well, maybe a "Clarke Omniputer" *could* get a job writing for the observer?
Slashdot Mirror
Actually, launching a rocket into the sun is extraordinarily difficult, and I think is still beyond our abilities (please, some of you rocket-scientist types out there correct me if I'm wrong....)
The problem is, we're orbiting the sun, and so is anything we launch. Earth's orbital velocity is pretty high (29.8 km/sec according to this).
Any rocket that hit the sun would have to first kill its initial orbital velocity of 30km/sec, or it would "miss" the sun and whip around the sun in a comet-like orbit.
Thank you!
/. - honest) by people who haven't got a clue what they are talking about.
I was wondering when someone who knew what they were talking about would come along. I have never seen so many highly-modded posts (even on
If only I had some moderator points, I'd be modding DOWN all the posts here that are complete bullshit.
Moderators, please don't just mod someone up because they *sound* authentic.
The problem is Frontier and First Encounters (Elite 2 and 3) are DOS only... go to http://www.jaj22.demon.co.uk/ to download a hacked version of Frontier - binaries for Win32 and Linux are available.
If you've got an interest in astronomy, check it out - Travel through realistic solar systems, explore, and complete missions. The game is very open ended, and although it predates 3d acceleration, the techniques it uses to render fractal planet surfaces has never been used elsewhere (as far as I know) and still works well.
Can you please provide some links to back that up? 1/3rd seems a little high....
;)
Not that I'm saying anyone here would make up statistics on the spot, y'know...
Hey, what about the NZ-nuclear free issues then?
We held out on not allowing nuclear powered or armed US ships in our waters, in spite of immense diplomatic and economic pressure.
Sure, the DCMA isn't going to be such a powerful issue, right now, but how will the public feel in a couple of years, the way things are going?
Actually, Peter Jackson *has* arranged for the special edition to be shown in the Embassy theatre, here in Wellington, New Zealand where the film was made... But only once, the night before the special edition DVD is released.
The Embassy theatre is a kick-ass old theatre that has been refurbished recently. Its got an amazing sound system and what I was once told is the biggest screen in the southern hemisphere. It used to have nearly 1800 seats!!!
Apparently Peter wanted the world premier of FOTR to be held here, but New Line Cinemas said no (they wanted it somewhere on the map, like, say, London...) but agreed to let Peter show the special edition here instead. Some info about the embassy theatre can be found here
I had an opportunity to get tickets for the screening, but I decided against it - we're talking about FOUR hours of sitting on your arse without moving, once you include the previews etc. Maybe if they had an intermission...
Also, apparently Peter doesn't like the term 'Directors cut' because he always intended to make two versions, the full version and a shorter version for the box-office.
Hey regarding compilers.... Does anyone have any info about how .NET will go on Itamium, or even Java?
.Net and Java are all about JIT compiliation of some intermediate bytecode to native machine code as needed.
.Net assemblies at runtime will have a higher performance overhead on Itamium, if the JIT compiler wants to extract the best performance out of the chip?
Think about it,
Itanium is all about moving the complexity of moving out-of order execution and stuff onto the compiler at compile-time instead of doing it at runtime with silicon.
Doesn't this imply that JIT compilation of Java Bytecode or
Has anyone here seen/done any benchmarks for this?
No, sorry but I dissagree.
A clever VM system is more important than ever, when you combine it with an effective disk cache.
Yes, Ram is cheaper and faster than ever, but stopping your OS from using a swap file/partition is gonna stop your OS from efficiently using your ram.
Your machine should be allocating as much memory as possibe to a disk cache, even if this reduces the available memory to the extent that active processes start paging, because the swap file paging is optimised by the disk cache too.
It is usually better to swap out pages and keep your cache large than to keep rarely used pages in memory at the expense of cache, because even if you need those pages they will quite likely be in the cache.
Even if you have a shedload of memory (especially so!) you will get better use of your memory if you use some of it as a disk cache than if you don't page rarely-used pages to disk.
No hostility intended.
I dissagree, I think MS deserves MUCH more than they get. They are primarily a marketing company, and yes, they make some good things, but they always try their hardest to lock you in once you bite - classic carrot-on-a-stick technique - they INVENTED embrace and extend.
I think the poor security record of products like NT/2k is *very* dissapointing, when you consider they COULD have been such good products. NT's security is pretty comprehensive and well thought out, and leaves linux in the dust for features, but they missed the last hurdle - e.g. out of the box installs of NT and 2K give FULL file permissions to ALL the system files to everyone by default, and even worse, all of the system daemons (IIS etc) run in the security context of local admin! (localsystem). That way, something as simple as a buffer overflow in IIS can give you local root access. There is no need, yet I've never managed to get the IIS service to run as anything other than localsystem (and I can't find any docos relating to this at MS either - anyone help?)
I think something that both Microsoft and the OEM's count on is the time it takes from the time a bug is found until the time the bug is exploited! In the case of Code Red and Nimda I think that time spanned months.
No, in code red's case the discoverer of the bug didn't go public until the patch was out, so the delay was effectively zero. Nimda used up to 7 different holes, but these were also patched very quickly.
It was months until the actual automated exploits and worms started appearing to exploit these well known holes, there was no excuse for being caught by Code Red or Nimda.
If there is one thing you can't accuse microsoft, its not being prompt to release patches for their holes... its just that their patches are requred far to frequently...
I can't find any info on MS's site right now, but I'm sure that OEMs that supply W2k datacenter are required to have a support team ONSITE at MS's campus 24/7.
;)
This article raises a very good point, but Microsoft's idea behind datacenter was they hat total control over the hardware environment, and they made sure OEMs would stand behind it too, so I'd be very surprised (and dissapointed) if the OEM didn't contact their customers *immediately* with patches whenever there was a hole (and I'd guess they are pretty busy too
... He's got a real pair of clangers for doing this and releasing it! I really hope he stays anonymous.
He's done a very thourough job of reverse-engineering too. Read his README file, very interesting... some quotes:
"One very important effect of this scheme is that Microsoft fully controls who gets to write modules that interact with the basic Microsoft media modules. Without a certified public key (and the corresponding private key) it is impossible to write a compatible DLL that interfaces with their code. Since Microsoft controls the issuing of certified public keys, they also have complete control over who is allowed to make compatible and competing products. Microsoft's reputation for being generous to competitors is well-known, so this effectively gives Microsoft a technically guaranteed monopoly power."
And his 'Messages' at the bottom:
"Microsoft: You guys have put together a pretty good piece of software. Really. The only real technical flaw is that licenses can't be examined for their restrictions once they are obtained. My real beef is with the media publishers' use of this software, not the technology itself. However, it's easy to see where software bloat and inefficiency comes from when this code is examined: every main DLL has a separate copy of the elliptic curve and other basic crypto routines, and parameters passed back and forth between modules are encrypted giving unnecessary overhead, not to mention all the checks of the code integrity, checks for a debugger running, code encryption and decryption. Perhaps you felt this was necessary for the "security through obscurity" aspect, but I've got to tell you that this really doesn't make a bit of difference. Make lean and mean code, because the obscurity doesn't work as well as you think it does.
Justice Department: Maybe this should really be addressed to the state officials, since it looks like the current U.S. administration doesn't care too much about monopoly powers being abused. But for whoever is interested, there is a very serious anti-competitive measure in this software. In particular, for various modules of the software to be used, you must supply a certified public key for communication. Guess who controls the certification of public keys? Microsoft. So if someone wants to make a competing product, which integrates well with the Windows OS, you will need to get Microsoft's permission and obtain a certificate from them. I don't know what their policy is on this, so don't know if this power will be abused or not. However, it has the potential for being a weapon Microsoft can use to knock out any competition to their products."
Well said.
That kind of machine would probably be able to run a recomplied version of win95
;)
And why on *earth* would you want to do something as silly as that??
</me shudders...>
And I thought people who crammed linux on iPAQs were masochistic...
You're really thinking of breaking new ground, aren't ya
Win95 does not have a preemptive kernel (it isn't even reentrant). NT might. Solaris does. Linux does with this patch.
Yes, NT's Kernel is preemptive, with pretty fine locks - this is why it scales quite well on MP machines.
The main reason Win9x is so crap at multi-tasking is most of the kernel isn't re-entrant, even though it is pre-emptable, 'cause of all the ugly 16-bit code in there.
Thats why if one process in win9x locks up, quite often everything else gradually locks up too, as other processes can't get to the kernel until the original process unblocks.
Win9x "multi-tasking" is such an ugly kludge it shouldn't really be called that at all.
The overall poor stability of Win9x is more to do with unprotected memory than multi-tasking cockups tho.
Windows 2000 can change favor from background to foreground processes on the fly (right click 'My Computer' and check out the properties)
That doesn't change NT's pre-emption behavior dude. NT automatically boosts the priority of the process that owns the topmost window, to make the UI Snappier... that option just turns this on or off.
NT/2K also uses varying process quantums depending on if you are using it as a server or workstation, but I don't think the favour background/foreground processes option tunes this... I'm pretty sure the quantum length is the only (major) difference between NT server/workstation or W2K pro/server. Longer quantum = lower context-switching overhead = more throughput.
On NT you can't kill a process when it is in the kernel/device driver either... I get that a lot when I put a bad CD in my drive and try and read it. The app hangs, and I try and kill it only to be told "this task cannot be ended at this time".
Grrr.
Yeah, you can start a process as another user, but still in your regular session (like NT and 2k) or, new to XP, you can start another session as a different user, on a different desktop while the 1st user is still logged on (with programs running and all)
This, and the cleartype support are about the only things I think XP has got going for it. I'm gonna stick with 2k unless MS releases a method of un-installing all the crap that is built in - Firewall, messenger, moviemaker etc etc etc.
Ohhh.... that sounds like a troll, but I just can't resist biting...
My MacOS 7, 8, or 9 machine has a much more responsive interface on a 75-MHz machine than Gnome on a 500-MHz Linux box
Uhh.. and thats with WHAT apps running concurrently? You gotta remember, GNOME is quite a bit more complicated than MacOS, and GNOME is working through a shedload more layers of abstraction (X, display drivers etc...)
In MacOS<10 (or Win3.1) if a misbehaving app wanted to hog the CPU, then the interface just doesn't respond. The whole point of pre-emptive multitasking is that if the app doesn't play nice, you still can do other things.
Anyway, the your whole point is kinda... pointless, as apps running on a pre-emptive OS still are probably yeilding the CPU voluntarily if the system is under a light load. It isn't until things start really working, or until an app starts hogging CPU that it is pre-emptively sheduled out against its wishes.
a batch process started up on my UltraSPARC today that rendered the box unusable...
quite possible, if it had a high priority. At least you have the option of changing priorities, on a non-preemptive OS there is no concept of priorities, each app can hog as much CPU as it likes!
But I guess you're happy using MacOS 7-9 instead of MacOS X, or Win3.1 instead of Win9x. Win9x barely qualifies as a pre-emptive OS tho, most of the kernel is single-threaded, so apps tend to block each other too much - try NT4/W2k.
No, it looks like having a large moon may be essential to stabilize the orbit and climate of a planet - check out Not All Habitable Zones Are Created Equal from SpaceDaily
Basically, in 1993 someone looked closer at mars's orbit, and found its axial tilt isn't constant, but varies from 0-60 deg, over a period of 157,000 years!
Needless to say, an axial tilt of 60 degrees is going to royally screw up the climate. Turns out the moon is stabilizing earth's orbit, our axial tilt varies 2.5 degrees every 41,000 years. It has been calculated that without the moon, we would wobble between 0 and 85 deg tilt... lucky eh?
According to the article, Earth is actually at the inner edge of the habitable zone, and the only reason mars is so cold is it is too small to hold an insulating atmosphere.
"verging on artificial intelligence"
Well, maybe a "Clarke Omniputer" *could* get a job writing for the observer?