Which of these CPUs is most productive?

[Rodrigo]

Originally Posted by mdettweiler

I'd guess an SSD. Taking a quick look at Newegg, I see that you can get an 8GB SSD for about the same price as the hard drive in my hypothetical configuration--for a dedicated cruncher, that would definitely be the way to go. (Same price, but MUCH faster, and a dedicated cruncher doesn't need much space.)

Wow, I did not realize that SSD's came in such tiny sizes. And presumably the OS would have to be a small Linux version rather than Windows. (OK, maybe Windows 98.)

A quick question -- how does using an SSD speed up crunching? Maybe I've got it wrong, but I thought that the drive is involved only every so often as Prime95 saves the last X minutes' worth of work.

Thanks again!

Rodrigo

[mdettweiler]

Originally Posted by Rodrigo

Wow, I did not realize that SSD's came in such tiny sizes. And presumably the OS would have to be a small Linux version rather than Windows. (OK, maybe Windows 98.)

A quick question -- how does using an SSD speed up crunching? Maybe I've got it wrong, but I thought that the drive is involved only every so often as Prime95 saves the last X minutes' worth of work.

Thanks again!

Rodrigo

8 GB should actually be plenty for most modern Linux distributions; even Windows 7 should be able to fit (I have a Windows 7 Enterprise trial version installed on a virtual machine and it only takes up ~5.5 GB).

The main advantage of SSDs is that they speed up the boot process, which is very disk-bound. For this reason, people will sometimes put their operating system and programs on an SSD (if you're going to use it for programs, you'd want at least a 16GB), and put their data on a much larger hard drive. The difference as far as crunching speed goes would be nominal, but it would make general operation of the system MUCH faster.

[Rodrigo]

Originally Posted by Uncwilly

A USB thumb drive. Most modern BIOS'es can boot from the thumb. They are way cheaper than a mechanical and use less power. If the machine is networked the critical data can be backed up easy. If you can boot from LAN, then you don't need that either. PrimeMonster used to boot a *nix from LAN and ran it from a RAM drive. Each node had a spot on the server's HDD for data storage.

Uncwilly,

So, until we hear back from Harvey, would it be reasonable to guess that he has a nearly bare-bones system (CPU + RAM and no HDD, floppy, or optical drive) used solely for crunching? That would be kinda neat.

Rodrigo

[Uncwilly]

Originally Posted by Rodrigo

A quick question -- how does using an SSD speed up crunching? Maybe I've got it wrong, but I thought that the drive is involved only every so often as Prime95 saves the last X minutes' worth of work.

Originally Posted by mdettweiler

The main advantage of SSDs is that they speed up the boot process, which is very disk-bound.

The main advantage of using a USB drive is that one can get a 3 pack of 4GB for ~$15, out the door (after taxes, etc.) That is certainly cheaper than one can buy an SSD or HDD. More crunching bang per $. Why pay for a case if you don't need one, or a keyboard, mouse, display, optical drive, etc.? GHz/days per $ can be influenced heavily by cutting the $ per node. Use linux not Win, save enough to buy another node after building about 6.

Originally Posted by Rodrigo

So, until we hear back from Harvey, would it be reasonable to guess that he has a nearly bare-bones system (CPU + RAM and no HDD, floppy, or optical drive) used solely for crunching?

It is quite common. I was trying to dig up the link to some monsters/farms.

[Rodrigo]

Originally Posted by mdettweiler

8 GB should actually be plenty for most modern Linux distributions; even Windows 7 should be able to fit (I have a Windows 7 Enterprise trial version installed on a virtual machine and it only takes up ~5.5 GB).

mdettweiler,

I guess that the Windows bloat isn't as great as I'd thought. It's good to know that you can actually run a current MS system on a thumb drive.

Learned a lot tonight, thank you!

Rodrigo

[Rodrigo]

Originally Posted by Uncwilly

The main advantage of using a USB drive is that one can get a 3 pack of 4GB for ~$15, out the door (after taxes, etc.) That is certainly cheaper than one can buy an SSD or HDD. More crunching bang per $. Why pay for a case if you don't need one, or a keyboard, mouse, display, optical drive, etc.? GHz/days per $ can be influenced heavily by cutting the $ per node. Use linux not Win, save enough to buy another node after building about 6.

It is quite common. I was trying to dig up the link to some monsters/farms.

Uncwilly,

Hmm, this is a new concept for me. So then these computers run off a LAN? Without a display, a mouse, or even a keyboard (and not even a case?!), I can't imagine how else one would input commands or even know what they're up to at a given moment.

Rodrigo

[Uncwilly]

Here is a link to an old project that someone did.
http://web.archive.org/web/200306221...com/index.html

[mdettweiler]

Originally Posted by Rodrigo

Uncwilly,

Hmm, this is a new concept for me. So then these computers run off a LAN? Without a display, a mouse, or even a keyboard (and not even a case?!), I can't imagine how else one would input commands or even know what they're up to at a given moment.

Rodrigo

Generally, such a rig is controlled remotely (usually by SSH if it's running Linux, which is usually the case).

The OS could be booted from either a USB drive or from the LAN. With a USB drive, it would be like a live CD setup, except customized such that it automatically starts up with the appropriate computer name and (possibly) automatically starts prime-crunching clients as appropriate. A LAN netboot is more complex: you'd need to set up a netboot server somewhere on your network (a "real" computer with special server software running on it) which would keep stored OS images, again in the same vein as a customized live CD. The individual nodes' BIOSes would be configured to boot off the network, i.e. the first thing they do when they power up is start searching the network for a compatible netboot server. When one is found, the node downloads the OS image from it, boots up, and runs whatever programs the image is configured to load at startup. (Again, these could be accessed remotely by SSH if any direct configuration is needed.)

A netboot setup is probably only worthwhile if you have a lot of dedicated crunching nodes, due to the complexity of the setup. Probably a better bet for the more casual cruncher is to go the route of a bootable USB drive.

Note that even with a dedicated crunching box, you may want to have an actual disk (SSD or hard drive) to give added flexibility. For instance, a friend of mine on this forum has a "small" farm of 10 dedicated crunching machines, which I consulted on the setup of. Since he's not too particularly tech-savvy, we ended up forgoing the more exotic possibilities (netboot, USB, etc.) and built complete, but nonetheless Spartan computers. Each box has a CD drive, hard drive, and case, but we picked the cheapest ones availalble at the time. From there, we could have still made the boxes headless (no monitor/keyboard/mouse) but he wasn't comfortable with going all-command-line so we ended up installing Ubuntu Desktop. He has them all in his basement with three or four monitors shared between a few boxes each via KVM switches.

In my friend's case, we've sometimes put the computers to dual use as servers for the prime search project we co-admin (No Prime Left Behind, in the Prime Search Projects section of the forum) in addition to crunching. (Last year he got another box with slightly higher-grade parts and a larger hard drive to serve as a dedicated server; nonetheless it still crunches on 3 of its 4 cores on the side. ) He's also used the boxes at various times to back up files from some of his other computers. This flexibility wouldn't have been possible if the boxes didn't have disk drives (though to some degree it might have worked with USB drives if they were large enough).

[lavalamp]

If you want a GUI, you can set all the computers up using a monitor, keyboard and mouse, but then unplug them when you're done. This way the machines don't take up a huge amount of room, and you don't need to buy lots of monitors, keyboards and mice. All they should need is power and a network cable (I GREATLY prefer wired over wireless).

Then you can VNC into them from your main desktop PC. There are lots of VNC applications, many of them free and open source, they work on all kinds of different platforms so you can VNC into a Linux box from a Windows PC no problem.

VNC allows you to see what would be on their screen, if they had one attached (or even if they do have one attached but you're too lazy to go there ).

[Cruelty]

From my experience - if you start a linux box without monitor attached then you won't be able to use VNC. I have found solution here.

[Harvey563]

Sorry to take so long to get back to the thread. I just use a regular thumb drive loaded with linux. No hard drives, no SSDs. I just use kvm switches to slave multiple machines to one monitor and keyboard, which is easier than networking, although not as elegant.