Different "Janus" at Lawrence Livermore
on
Microsoft Janus
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· Score: 1
I remember seeing something about a product called "Janus" at LLNL back in 1987. It was some sort of combat simulation program for use by the Army, I believe.
Janus has probably been used as a name for many, many different projects.
Minor correction: EMC and Clariion are separate companies. With that in mind, my post makes a bit more sense. Hence, EMC's sales force is what you get when a competitor's system goes down. EMC's customer-service is what you get if EMC equipment has trouble.
Also, redundancy is the key to any high-end storage system. While the individual system will have redundancy (mirroring, raid, etc.), you also want remote mirroring to a separate storage system, possibly in another city for disaster recovery.
My obviously-biased viewpoint is that while you may have had some trouble with your EMC setup, in general, EMC is more reliable, faster, and more proven than solutions from any other company.
Part of the fun of Ask Slashdot questions is that they not only answer the original question, but they explore all the related tangents.
So if you're interested in fibre channel, multi-terabyte storage systems, media servers, and such, there's probably going to be a lot of interesting stuff here.
And as to your point, Linux may be a good solution if they can figure out the server architecture. They're already talking about using a cluster of servers, so the CPU power isn't a big issue. I wouldn't assume that not knowing about the level of fibre channel support indicates that someone is clueless about Linux in general.
You should be aware that Ext2 tops out at 1TB, though that may get fixed.
Also, when dealing with large Ext2 file systems, they take forever to fsck, mainly due to the number of inodes. You can help overcome this by reducing the number of inodes. For example, if you know that the average file is 10MB, then maybe only have one inode per MB (instead of one per 4K). You should also use sparse superblocks (which requires a 2.2 kernel).
Generally, it is a good idea to have multiple servers in case one goes down, but it also makes sense to consolidate storage. Storage systems like the EMC Symmetrix or Clariion raid arrays are designed to *never* go down. (When the Clariion does go down, the EMC sales force will be there.:) EMC can even do live upgrades of the embeded code. (Imagine upgrading to the next Linux kernel without rebooting!)
The point is that you can't get the performance and reliability out of a small storage system that you can out of the enterprise storage systems. Of course, in some cases, you can build a system based on replication of the data, which for static data may work, but often as not, when all the costs are factored in, you're better off with a consolidated system.
You might be interested in GFS. It's a cluster filesystem. The idea is that a bunch of machines all talk to the same drive(s), instead of going through a single server.
There are two places to look for Linux fibre channel support. First, at the University of New Hampshire, someone is the leading force behind fibre channel drivers. Second, at the University of Minnesota, the GFS project uses fibre channel for their Linux-based file system work.
Note, I work for EMC, which also makes large multi-terabyte storage systems.
That's a good point, but it should be taken a little farther.
In order for a democracy to work, you need an informed electorate. However, current conventional wisdom in the USA seems to be that people should vote. There's no suggestion on that saying that only poeple who have thought about the issues should vote. I even heard on election-time "public service" announcement saying that it doesn't matter who you vote for, just vote.
That's horrible.
People who aren't going to take the time to understand which party or candidates best reflect their concerns shouldn't vote. Even further, people who don't see those differences as being important enough to go out of their way to vote shouldn't vote.
Voting should be an inconvenience.
Voting is power, and power shouldn't be used frivolously.
As mentioned, the leading problem with cracking the DVD Content Scrambling System is that the algorithm is secret. It's not even clear that they use a real encryption algorithm, though it may just be called "scrambling" intead of "encrypting" for political reasons (for sales in countries like France).
It will eventually be broken.
The key is either a leak from an insider, or reverse engineering of a software DVD player.
If I wanted to break it, I would find a way to run a software DVD player under a debugger. Leading candidates include Wine (with some additional DVD driver support, it might work) and VMware (I haven't looked into it). The other option would be to simply disassemble the binary, though that might be more work.
Personally, I don't want to see it broken until DVDs are outselling VHS tapes. Until then, cracking CSS might slow down adoption of DVD (if fewer titles are released).
What we need now is a page with all the slashboxes on it. I suppose I could just go and turn them all on, and turn off the ones I don't like, but I would prefer to have a page with all of them where I can select which ones I want.
So what would it take to get Linux branded as Unix?
Of course, that would only apply to a given release of a given distribution, but politically, it would be a big step. I'm sick of hearing that Linux is a Unix-like OS, as opposed to being just a version of Unix.
Maybe Red Hat, Corel, or Caldera would fund Unix branding?
I have trouble calling it a microkernel with a straight face, since it's so large.
I have trouble keeping it running for more than a few hours, since I run real Mach code (not just stuff that talks to the Unix server). I've managed to patch the bugs that caused me the most trouble (in the external memory manager code, among other places), and they're in the mainline Open Group codebase, for all the good that will do anyone.
We did do a complete re-write of Mach in C++, called mk++. That was a nice clean implementation; a good example of software engineering. Unfortunately, the plug was pulled just a few months before mk++Linux was to be released (as a CD-ROM accompanying a book).
That's true in general. There are only a few developers still working for TOG on some old DARPA contracts (mostly doing NT stuff). I'm pleased to see that the user community is keeping things going, though it would probably make more sense to get native Linux running on those systems only supported by mkLinux as a long-term solution.
Snail mail spam is a pain, but it is very different. First, the recipient of such spam doesn't pay for the priviledge of receiving it. Second, the Postal Service doesn't object to carrying it. Third, snail mail spammers have to pay a fee for each item they send, which acts as an incentive for them to target their mailings to only those most likely to be interested.
That in mind, I would consider the following reforms to be reasonable for bulk snail mail:
Rates for bulk mail should be such that commercial mail subsidizes other mail.
All bulk mailings must provide a phone number to call to be removed from the list (and it must be on the outside of the mailing).
Interesting point. This seems to be pretty clearly a case of interstate commerce, which is solely in the relm of the federal government, thanks to that much-abused clause in the Constitution.
Of course, the attitude of most lawmakers is to pass whatever laws seem politically useful at the time and let the courts think through the constitutional issues.
Watch out for legislation like this. Essentially, all it is doing is banning anonymity. This isn't about saying what you can or can't send, only that you can't do it with fake routing info.
It is probably aimed more at stopping people from sending spam that appears to be from slashdot.org or such, but I don't think they thought through all the privacy issues that it is treading very close to.
I've heard that some ISPs set up fake accounts and troll for spam, allowing them to kill all the duplicates that are sent to real accounts. Do they just post dummy messages with these accounts, or what?
Now what if they did that with the email addresses of all state and federal legislators?:)
I get tons of spam that has non-forged routing and email information, but the problem is that it comes from temporary accounts from AOL, or references free email accounts at YaHoo or Hotmail.
What we need at a minimum is something that will ban sending unsolicited commercial e-mail from accounts without the permission of the company that issues those accounts.
Personally, I would ban all unsolicited commercial email.
Who cares what distribution they used? What matters is the versions of the kernel and servers. Since they had people from Red Hat there to tune the system, it made sense to use the distribution that they felt most comfortable with.
Distributions only matter in performance if you're not going to take the time to update and configure your software, or if you're not going to disable irrelevant services only provided by some distributions.
Arguing over distributions for benchmarks is like arguing over Gnome vs. KDE when you're not running X.
(Found at LWN.) This page is full of technical analysis of the Linux kernel and Apache, explaining a number of performance problems that the benchmarks brought to light, as well as solutions for many of them.
It sounds like a repeat test in another month or two would bring things even closer. With khttpd, we might even win.
Same here, though I had to terminate my service when I moved a month ago.
Of course, with these big national cable ISPs, it really helps if you mention the town you're in, in case the quality isn't all that consistent.
On the other hand, I've generally heard better things about MediaOne than RoadRunner, and @Home seems to have the worst reputation. I'm hopeful that the merger of MediaOne and RoadRunner won't result in problems over the long haul.
I read somewhere that the brains capacity was on the order of 13 TB. No links to back it up yet...
If you want to back up 13TB, you might start with EMC. We deal with datasets measured in terabytes every day, and are quite adept at backing them up without even taking them offline.
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I remember seeing something about a product called "Janus" at LLNL back in 1987. It was some sort of combat simulation program for use by the Army, I believe.
Janus has probably been used as a name for many, many different projects.
Minor correction: EMC and Clariion are separate companies. With that in mind, my post makes a bit more sense. Hence, EMC's sales force is what you get when a competitor's system goes down. EMC's customer-service is what you get if EMC equipment has trouble.
Also, redundancy is the key to any high-end storage system. While the individual system will have redundancy (mirroring, raid, etc.), you also want remote mirroring to a separate storage system, possibly in another city for disaster recovery.
My obviously-biased viewpoint is that while you may have had some trouble with your EMC setup, in general, EMC is more reliable, faster, and more proven than solutions from any other company.
Part of the fun of Ask Slashdot questions is that they not only answer the original question, but they explore all the related tangents.
So if you're interested in fibre channel, multi-terabyte storage systems, media servers, and such, there's probably going to be a lot of interesting stuff here.
And as to your point, Linux may be a good solution if they can figure out the server architecture. They're already talking about using a cluster of servers, so the CPU power isn't a big issue. I wouldn't assume that not knowing about the level of fibre channel support indicates that someone is clueless about Linux in general.
You should be aware that Ext2 tops out at 1TB, though that may get fixed.
Also, when dealing with large Ext2 file systems, they take forever to fsck, mainly due to the number of inodes. You can help overcome this by reducing the number of inodes. For example, if you know that the average file is 10MB, then maybe only have one inode per MB (instead of one per 4K). You should also use sparse superblocks (which requires a 2.2 kernel).
Generally, it is a good idea to have multiple servers in case one goes down, but it also makes sense to consolidate storage. Storage systems like the EMC Symmetrix or Clariion raid arrays are designed to *never* go down. (When the Clariion does go down, the EMC sales force will be there. :) EMC can even do live upgrades of the embeded code. (Imagine upgrading to the next Linux kernel without rebooting!)
The point is that you can't get the performance and reliability out of a small storage system that you can out of the enterprise storage systems. Of course, in some cases, you can build a system based on replication of the data, which for static data may work, but often as not, when all the costs are factored in, you're better off with a consolidated system.
You might be interested in GFS. It's a cluster filesystem. The idea is that a bunch of machines all talk to the same drive(s), instead of going through a single server.
http://www.globalfilesystem.com/
There are two places to look for Linux fibre channel support. First, at the University of New Hampshire, someone is the leading force behind fibre channel drivers. Second, at the University of Minnesota, the GFS project uses fibre channel for their Linux-based file system work.
Note, I work for EMC, which also makes large multi-terabyte storage systems.
That's a good point, but it should be taken a little farther.
In order for a democracy to work, you need an informed electorate. However, current conventional wisdom in the USA seems to be that people should vote. There's no suggestion on that saying that only poeple who have thought about the issues should vote. I even heard on election-time "public service" announcement saying that it doesn't matter who you vote for, just vote.
That's horrible.
People who aren't going to take the time to understand which party or candidates best reflect their concerns shouldn't vote. Even further, people who don't see those differences as being important enough to go out of their way to vote shouldn't vote.
Voting should be an inconvenience.
Voting is power, and power shouldn't be used frivolously.
As mentioned, the leading problem with cracking the DVD Content Scrambling System is that the algorithm is secret. It's not even clear that they use a real encryption algorithm, though it may just be called "scrambling" intead of "encrypting" for political reasons (for sales in countries like France).
It will eventually be broken.
The key is either a leak from an insider, or reverse engineering of a software DVD player.
If I wanted to break it, I would find a way to run a software DVD player under a debugger. Leading candidates include Wine (with some additional DVD driver support, it might work) and VMware (I haven't looked into it). The other option would be to simply disassemble the binary, though that might be more work.
Personally, I don't want to see it broken until DVDs are outselling VHS tapes. Until then, cracking CSS might slow down adoption of DVD (if fewer titles are released).
What we need now is a page with all the slashboxes on it. I suppose I could just go and turn them all on, and turn off the ones I don't like, but I would prefer to have a page with all of them where I can select which ones I want.
So what would it take to get Linux branded as Unix?
Of course, that would only apply to a given release of a given distribution, but politically, it would be a big step. I'm sick of hearing that Linux is a Unix-like OS, as opposed to being just a version of Unix.
Maybe Red Hat, Corel, or Caldera would fund Unix branding?
I recall hearing that The Open Group approved the use of "Unix" for a product that provided the right set of interfaces under NT.
Ugh.
Correct me if I'm wrong, but my understanding is that there never was a serious proposal for a "metric time" different from standard time.
I don't like Mach because it's bloated and buggy.
I have trouble calling it a microkernel with a straight face, since it's so large.
I have trouble keeping it running for more than a few hours, since I run real Mach code (not just stuff that talks to the Unix server). I've managed to patch the bugs that caused me the most trouble (in the external memory manager code, among other places), and they're in the mainline Open Group codebase, for all the good that will do anyone.
We did do a complete re-write of Mach in C++, called mk++. That was a nice clean implementation; a good example of software engineering. Unfortunately, the plug was pulled just a few months before mk++Linux was to be released (as a CD-ROM accompanying a book).
The Open Group also has ceased development.
That's true in general. There are only a few developers still working for TOG on some old DARPA contracts (mostly doing NT stuff). I'm pleased to see that the user community is keeping things going, though it would probably make more sense to get native Linux running on those systems only supported by mkLinux as a long-term solution.
That in mind, I would consider the following reforms to be reasonable for bulk snail mail:
Interesting point. This seems to be pretty clearly a case of interstate commerce, which is solely in the relm of the federal government, thanks to that much-abused clause in the Constitution.
Of course, the attitude of most lawmakers is to pass whatever laws seem politically useful at the time and let the courts think through the constitutional issues.
Watch out for legislation like this. Essentially, all it is doing is banning anonymity. This isn't about saying what you can or can't send, only that you can't do it with fake routing info.
It is probably aimed more at stopping people from sending spam that appears to be from slashdot.org or such, but I don't think they thought through all the privacy issues that it is treading very close to.
I've heard that some ISPs set up fake accounts and troll for spam, allowing them to kill all the duplicates that are sent to real accounts. Do they just post dummy messages with these accounts, or what?
:)
Now what if they did that with the email addresses of all state and federal legislators?
I get tons of spam that has non-forged routing and email information, but the problem is that it comes from temporary accounts from AOL, or references free email accounts at YaHoo or Hotmail.
What we need at a minimum is something that will ban sending unsolicited commercial e-mail from accounts without the permission of the company that issues those accounts.
Personally, I would ban all unsolicited commercial email.
Who cares what distribution they used? What matters is the versions of the kernel and servers. Since they had people from Red Hat there to tune the system, it made sense to use the distribution that they felt most comfortable with.
Distributions only matter in performance if you're not going to take the time to update and configure your software, or if you're not going to disable irrelevant services only provided by some distributions.
Arguing over distributions for benchmarks is like arguing over Gnome vs. KDE when you're not running X.
http://www.kegel.com/mindcraft_redux.html
(Found at LWN.) This page is full of technical analysis of the Linux kernel and Apache, explaining a number of performance problems that the benchmarks brought to light, as well as solutions for many of them.
It sounds like a repeat test in another month or two would bring things even closer. With khttpd, we might even win.
Same here, though I had to terminate my service when I moved a month ago.
Of course, with these big national cable ISPs, it really helps if you mention the town you're in, in case the quality isn't all that consistent.
On the other hand, I've generally heard better things about MediaOne than RoadRunner, and @Home seems to have the worst reputation. I'm hopeful that the merger of MediaOne and RoadRunner won't result in problems over the long haul.
How well does MS MediaPlayer work under Wine?
It's not an ideal solution, but it would work as an interim solution.
I read somewhere that the brains capacity was on the order of 13 TB. No links to back it up yet...
If you want to back up 13TB, you might start with EMC. We deal with datasets measured in terabytes every day, and are quite adept at backing them up without even taking them offline.
:)
[Yes, I work for EMC--it's a wonderful job.]