Auto Load in RAM

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12-01-2005, 03:42 PM
EBFoxbat

Auto Load in RAM

I have a ~1.8 Ghz computer laying around. I've been playing with Knoppix for a while. I'm just learning linux and have been reading alot about it.

I WONT install to the hard drive. So please (please?) don't refer me to that thread.

My questions are these:

1)Does running entirely from ram... as in "toram" have the same effects as from hard drive?

2)Can I copy the disk image, as is, to hard drive (permanantely) then upon each boot, copy from hard drive to ram?

I'd like not only to have the speed of running it out of RAM, but the convienence of not having to use the CD while I learn linux.

I'm sure I'll install a true hard drive distro soon, but for now I have literature and books on the way about knoppix so i want to stick with that.

Thanks for the help and feel free to refrain from n00b flames.
12-01-2005, 06:02 PM
lilsirecho

EB Foxbat;

The TORAM utilized in Knoppix is a boot method.

If you are already booted into the OS, trying to boot again with an installed CD image, is not a viable proposition.

Operating in RAM is always faster than using HDD execution.

I have 3GB of ram and have operated with RAMFS files to enable 1GB .vob files to run in RAM, thus avaiding the need to access HDD during execution.

I hope these comments are informative and helpful.

Best to you :D
12-01-2005, 06:28 PM
Harry Kuhman

Re: Auto Load in RAM

Quote:

Originally Posted by EBFoxbat

1)Does running entirely from ram... as in "toram" have the same effects as from hard drive?

Since Knoppix wasn't intended for installing to hard drive, there is no one simple answer as to what from hard drive means. There are at least three very different forms of Knoppix install, likely with many variations on same. The "poor man's install" basically keeps the cloop file in compressed form on the hard disk. The toram option (assuming that you have the memory to support it) loads the compressed cloop file into memory rather than continue to access it from CD, so in that sense it is simiar to a poor man's install, although obviously there are differences. And it is not at all the same as trying to uncomprress the cloop and dropping the whole file structure uncompressed onto the hard disk.

Quote:

Originally Posted by EBFoxbat

2)Can I copy the disk image, as is, to hard drive (permanantely) then upon each boot, copy from hard drive to ram?

You may want to look at both the poor man's install and also at boting from an ISO on hard dosk (a trick discussed in the remastering forum, since those who remaster often wish to test the ISO that they produce without the extra step of burning a CD until they have it working).
12-01-2005, 09:46 PM
EBFoxbat

Is there an easy way to store the decompressed (which is what like 2.5 Gigs?) on the hard drive. Then load that, from the hard drive, into RAM and run it from RAM?

Should I store an uncompressed version on a DVD then boot the DVD to RAM?

What I want to do is run as fast as possible from RAM, which means uncompressed. Obviously if I could load to RAM from the hard drive it would be faster than from a CD/DVD. I am willing to boot from a CD/DVD into RAM if that is the only option, as I don't expect to be rebooting all that often, I was just hoping for to forego the CD/DVD.

This is turing into, perhaps, the perfect excuse to build a bursting-at-the-seams-with-memory rig.
12-01-2005, 10:15 PM
Harry Kuhman

Re: Auto Load in RAM

Quote:

Originally Posted by EBFoxbat

I WONT install to the hard drive. So please (please?) don't refer me to that thread.

Quote:

Originally Posted by EBFoxbat

Is there an easy way to store the decompressed (which is what like 2.5 Gigs?) on the hard drive. Then load that, from the hard drive, into RAM and run it from RAM?

Storing the decompressed file to hard drive is, at least as I understand it, what most people mean when they talk of installing Knoppix to hard drive, exactly what you emphatically said that you would not do.

Running it all in RAM in an uncompressed form would take much more RAM than most people have. And it hardly seems wise to read it all from disk into RAM and hold it there when you actually don't run 95% of the things on the Knoppix disk every time you boot anyway. Why copy several games that you are not going to play, several different editors, an astronomy program, even multiple spread sheet programs and a few different browsers into memory if you are not going to use them? If you do run a program it is of course loaded into RAM when run, but certainly everything on the Knoppix disc should not be loaded into memory every time.

So my answer to this is two part: If you want everying in RAM as you now state it would involve a large RAM disk and copying everything each time you boot, but it would be foolish and I would not guide someone into doing it. And, as far as I'm concerned, the easy way to store everything in the cloop file in an uncompressed form is to install Debian, not Knoppix, and then install what programs you want or think you need. If that's everything in the Knoppix package list, well, that's your business; I would choose differently.
12-02-2005, 01:02 AM
EBFoxbat

1) I said I will not install it to the hard drive. What I really meant was I will not run it from the hard drive.

I realize it would take a large amount of ram. As I said, it could be a nice excuse to build a large-ram machine.

I also realize that I will not run most programs regularly. However, being in the learning phase, I will run most of them atleast a few times.

I do not plan on rebooting very often so waiting for the hard drive to write its OS to ram would be acceptable to me. Plus I do not think it would take very long even if 2+ GB of data were transfered.

I would also like to see what realworld benifits there are to running an OS off ram. I would imagine it could be very fast. I'm just trying to learn.

I was thinking maybe I would uncompress the Live CD. Then store the uncompressed CD as a (much larger) ISO DVD. I could then copy the ISO to the hard drive and write to ram every ensuing boot.

As I said before. I am learning and am resonably sure I will, in the not to distant future, run other distros (probabaly debian) but for now I will play with knoppix.
12-02-2005, 01:28 AM
lilsirecho

Puppy Linux runs exclusively in RAM. It is not a major-sized distro but is a Live CD which runs in ram.

Perhaps you could develop it in a way fitting to your approach...
12-02-2005, 11:26 AM
EBFoxbat

Quote:

Originally Posted by lilsirecho

Puppy Linux runs exclusively in RAM.

Thanks. I shall add it to my list of things to read about.

I just dream of someday when there is low-capasity (say 1gb) of solid state memory that transferest quickly to ram, where it is then run at ridiculous speeds.

Because of the speed the OS would have to be stable. I think it should be contained in it's own device, maybe PCIe16 or something. It should be seperate from system memory and applications and data. And it should start copying from solid-state to it's own RAM while the computer is working through bios.

It could be a huge step closer ro instant on. Especially if it took no longer than BIOS to bring up a fully working desktop.

Perhaps, when I am learned enough, I should work to such an end.
12-02-2005, 08:59 PM
OErjan

hmm, actually, uncompressing slows things down, as slowest part of a computer is the busses...
there has been "trials" on this forum before "proving" that compressed ran faster, last tread with this was this summer if i am not all wrong, certainly this was no earth shattering diference.
To make things intetresting, in some tests (general hardware tests) results seem to point to that more ram would improve things up to about 1.5-2G or so, perhaps as high as up to 2.5G, but not much (yes, some but curves flatten) beyond, this as the read/writes on most "regular" motherboard/CPU/memory... combos would be hard pressed to cope.
on the other hand, if you have enough money you can certainly buy better performance...
12-02-2005, 09:12 PM
Harry Kuhman

Quote:

Originally Posted by OErjan

hmm, actually, uncompressing slows things down, as slowest part of a computer is the busses...

NO. Uncompressing files on disc slows things down, since you can read the disc and decompress faster than you can read a larger uncompressed file. The disc is certainly much slower than the busses. There are even some cases where compression on disk will speed things up, but these are much less pronounced than when reading from an optical disc. But the busses are still not the bottleneck. But since whatever you run from RAM must be uncompressed before you run it, saving it in compressed form in RAM slows you down, but in the case of something like the Knoppix cloop file saves you a lot of RAM. STill, the only reason for the toram option it to free up the CD and speed things up; Loading everything into RAM in uncompressed form, used or not, just does not make sense.
12-02-2005, 10:13 PM
EBFoxbat

Quote:

Originally Posted by Harry Kuhman

Still, the only reason for the toram option it to free up the CD and speed things up; Loading everything into RAM in uncompressed form, used or not, just does not make sense.

Why not? There is NO faster way to access data currently than good quality ram on a high-frequency bus. There's just nothing faster short of custom hardware.
12-03-2005, 03:48 AM
Harry Kuhman

Quote:

Originally Posted by EBFoxbat

Why not? There is NO faster way to access data currently than good quality ram on a high-frequency bus. There's just nothing faster short of custom hardware.

Sure, RAM is fast. But it is a finite resource. And understand that when you talk about saving all of these uncompressed applications in RAM you are actually talking about saving them in a RAM disk; this is not the same as having them loaded into memory and running; execuiting any of these programs actually loads another copy of the program into other RAM memory where it can be executed, the RAM disk keeps it's copy. If you had too much money it might make some sense to save lots of programs that you want to run to RAM disk. But not the extensive Knoppix package list, which is a mix of many programs that are very unlikely to ever all be used by any one person.

Since RAM is a finite resource (even if you have too much money you have limmited RAM address space), there is another issue: If Knoppix ever has to use it's swap file because a lot of the RAM the system has is wasted holding unneeded stuff in the ram disk, then this will seriously slow down your application, not speed it up. And it does take the OS some overhead just to manage lots of needless stuff in the RAM, not a lot untill swapping starts but still it is an impact. (I actually have seen some some operating systems that would slow down if you gave them too much RAM memory because they spent too much time mannaging all that space.) If you feel you just have to run from a RAM disk, my advice would be to copy what applications you tend to run to it and leave the rest on disk, where you can still get them if needed. Or even build a system that tracks and loads frequently accesses programs.