Physical Memory for Most Linux Distributions

[DavidMD]

Hello, everyone.

I have asked a similar question before, but I cannot locate the thread, so please forgive my repetition.

I have gotten a general consensus in forum replies that, even if I do memory-intensive work on my Linux workstation, 1.0 GB of RAM is quite sufficient, and that adding 512-MB of RAM would be "a total waste of money," to quote one respondent -- and not improve performance at all.

I have read other opinions yielded by Google/Linux searches and personal messages that an additional 512 MB of RAM would be of benefit, and that "one can never have too much RAM or hard disk space," as the old truism goes.

Can I assume that 1.0 GB of RAM, although on an MSI 845 Ultra-ARU motherboard (i.e., slow DIMMS compared to modern motherboards), will serve my needs adequately and that adding 512-MB of RAM would not help at all?

I have, of course, the swap partition, which I did use some with 1.0 GB of RAM when running SuSE Linux Professional, but I could have made a stupid configuration error that lead me to "waste" physical RAM. :p

Before I install the new hard drives, video card, and Debian "Etch" on my (now) Linux-only workstation, I just wanted to make sure that I am "all set," regarding physical RAM and that adding RAM will not help performance.

(The processor, motherboard, and RAM in this machine are hardly "state of the art," although the specifications seemed impressive four years ago when I built this machine; my 2.0-GHz Pentium-4 processor does not even support hyperthreading.) ;) I am happy, however, finally to have a Linux-only computer, but I want to optimize performance.

Thank you very much, in advance, for your time, help, and patience! :)

Cordially,

David

[dkeav]

if you are hitting swap, then you are taking a performance hit, the key is to find the sweet spot so that you have plenty of memory to try and lower how often you are swapping, and also how much money you have invested

1gb is usually plenty, but this also depends on what you do with your machine, i know that say je_fro and myself have 4gb or ram, and both of us still require quite a bit of swap and hit it often, that involves a lot of video editing, encoding, 3d modeling and rendering though, so mileage may vary

i would do whatever process you think you need the extra memory for and watch your swap consumption, but realistically 2gb is more or less the new 1gb, and with ram prices dropping all the time, 2gb is rather cheap to have, so if you can get an extra 512 stick, i dont see any reason to not put it in there if you want

if it helps your performance when you need it, then it did its job, if it doesnt HELP, then it certainly isnt hurting

[XiaoKJ]

I concur. If you are hitting swap at any time when you are only running normal apps, then an upgrade is fine.

Moreover, linux will never waste resources. You will definitely stand to benefit from every bit of something you put into linux, esp ram and cpu power. linux will just cache/do something with the excess.

However, please do remember that there is the law of diminishing marginal returns. Don't go out and buy so much you never use them.

Personally, 1 Gib of ram is enough for me right now. But if you want your machine to last longer, the extra 512 Mib is just fine. I would think that it is a good investment if you have the spare cash.

[bwkaz]

Yeah, I've cached the whole NTFS tree from a 160GB drive in my 2GB of RAM before. It really helped when the disk that the NTFS tree was on was failing, and taking several seconds to retry every request. That FS cache basically saved me having to waste fifteen minutes searching the tree several times for various different file types. ;)

(A friend owned the failing drive and had XP on it, and wanted to copy as much off as he could before it died permanently. The cache didn't help when I tried to copy the actual files off, but it did help -- a lot -- when I was using du to figure out how much space was used in each subdirectory. I never use most of that 2GB otherwise, but I was sure glad I had it that day.)

[DavidMD]

Greetings, dkeav, XiaoKJ, and bwkaz! :)

Thank you, each, very much for your replies! I very much appreciate your advice.

I am not sure why I was using the swap partition while I was running SuSE Linux Professional, but I assume that I will run into the same problem with Debian GNU/Linux 4.0 ("Etch"). (I was running some 'cron' jobs, but they were simple ones, such as regularly and automatically setting the system clock via the closest, most reliable NTP (http://en.wikipedia.org/wiki/Network_Time_Protocol) server, and regularly checking a POP3 e-mail account for new messages. I was manipulating some large images with The GIMP, as I tried to learn The GIMP, after using Adobe Photoshop since 1994. If I can get scanner support to work with The GIMP, then my "raw," starting images will be quite large, because it is always easier to edit a large image and then reduce its size.)

Without boring you too much with the details of my personal life, I have spent most of the past three days (every day this week so far, in other words) helping out my uncle, with whom I am very close, who has stage-IV (terminal) cancer -- although I did have an interview Tuesday morning for a contract technical-writing position with Bridgestone, which has its main headquarters here in the Nashville, Tennessee (USA) area. Today, I got up at 4:00 AM and took my uncle to the outpatient area of the closest hospital for a two-unit (one liter) blood transfusion; his hemoglobin count has been plummeting.

I did do some on-line price searching for 512-MB -- and even 1.0-GB -- 184-pin, PC2100, DDR DIMMs (non-ECC, 2.5 volds, 266-MHz, with SPD CAS 2.5 latency). This type of DIMM is compatible with my four-year-old, but rock solid MSI motherboard and self-built system.

Note: All of my research back in 2002, especially about Linux hardware compatibility, before I built the box, seems to have been worth the effort and time. Of course, focusing on Linux compatibility and running Linux are probably why the computer is still serving me well. :p I much prefer this humble box to the fast (but poorly ventilated), used, 3.0-GHz, Pentium-4 Dell tower, with hyperthreading and SATA, that I bought early this year. (In addition, I am emotionally attached to the machine I built myself, if that comment makes any sense!) :rolleyes:

__________ Aside __________

Financial Woes of Life: Unfortunately, just after leaving hospital late last evening with my uncle, I started my car to discover that the battery light came on after about twenty seconds. A trip to the local AutoZone revealed that my battery, despite being the one that came from the factory in my then-new 2001 car, which I just paid off in October, was fine -- but my alternator was dead. (The battery should not be lasting this long, but -- of course -- replacing the alternator is a huge expense compared to a new battery!

After my uncle got his blood tranfusion today (before which his hemoglobin count was only 8.0), he actually drove me to my house, so I could get my car, and we went to his trusted, skilled, and honest mechanic. My uncle told me yesterday that he would buy me a new battery; I told him that the battery had held up much longer than expected, and that I would find a way to replace the battery.

Today, he paid his mechanic for replacing my alternator, which was no small sum, and I told him that I consider his generous act a loan that I will repay after I get a new technical-writing job.

Ironically, yesterday, I was "pricing" additional RAM for my Linux-workstation, and then my car alternator failed last night!

Don't you just love life's capricious twists? :rolleyes:

____________________

OEMPCworld.com has a 512-MB DIMM for $59.85 (US), with free shipping, guaranteed to work specifically with my MSI 845 Ultra-ARU (MS-6398) motherboard. They do not have a 1.0-GB DIMM.

TigerDirect.com has a PQI 1.0-GB DIMM that matches my motherboard's specifications for $119.99 (US), also with free shipping, I believe.

ArchMemory.com offers a "major-brand" 1.0-GB DDR226 DIMM, but at $129.00.

Of course, in none of these situations do I know who actually makes the DIMMs or the memory chips. I assume that most memory shoppers are in the same situation.

These prices are the least expensive ones that I was able to find, except for a 512-MB DIMM at Newegg.com for about $50.00 that had three reviews, two negative and one positive -- so I am ruling out this "bargain," based upon the principle that "you get what you pay for," and memory at that price seems "cheap" in more aspects than price alone.

I have three DIMM slots, two of which are occupied by 512-MB DIMMs, but my research indicates that I can install either a 512-MB DIMM or a 1.0-GB DIMM, with a maximum motherboard support of 2.0-GB.

Assuming that I soon become flush financially, do you think that a 512-MB DIMM is enough additional physical RAM? I do not want to add more RAM than I can use (and I assume that too much RAM would literally go unused), but I am going to continue using this self-built computer to run Linux for quite some time, extending its life with new hard drives, a new video card, and -- ideally -- the additional RAM.

My goal is to be able to do all of my necessary computing projects using Linux ("Etch," at this point, although Debian is new to me). I still will use my G4 Power Mac for certain applications.

I would prefer, however, to keep Windows XP Professional around on the used Dell Dimension 8300 that I bought early this year for work related to technical-writing, although I will not upgrade from Office XP Professional to 2003 or the upcoming 2007 monstrosity office suite from Microsoft, even if it means that I cannot do any technical-writing work from home (unless my employer supplies a laptop, which is doubtful for a contract position, and I have only one possible full-time position). I plan to leave the Dell Dimension 8300 ("Windows computer") turned off most of the time, although I need to control it and the Linux workstation with a KVM.

Essentially, I want to be able to stop using Windows, except in cases in which I am literally forced to do so! :) I will therfore be investing considerable time, effort, and patience in installing and configuring Debian GNU/Linux. (In the future, I hope to build a new, fast Linux workstation -- probably by rebuilding my current workstation -- but that time will not occur soon.)

Do you think that an additional 512-MB of RAM is enough, even if I get into audio and video editing? Should I hold off until I can afford to "max out" the RAM in my self-built Linux workstation to 2.0-GB of RAM?

Finally, the Linux workstation currently has a 2.0-GHz, Pentium-4 processor without hyperthreading. The motherboard specifications state that the fastest processor that I can add is 2.2-GHz, although the information on OEMPCworld.com gives the maximum speed as 2.4-GHz+; I have absolutely no idea what the "plus" means.

In addition, I have read several articles this week stating that many computer users are being "brainwashed" into buying the newest, fastest processors and video cards, when adding RAM is a more cost-effective upgrade, especially for Linux, because it utilizes system resources so efficiently! The articles make sense to me.

I apologize for the absurd length of this reply, and for the digressions.

Thank you, very much, for your time, patience, and advice! :)

Cordially,

David

[psych-major]

FYI - I discovered the hard way that Ubuntu 6.06 had an issue whre it can't boot on a system with more than 2GB memory. I believe this was fixed in 6.10, but I haven't bothered to test it...

Also, doesn't Linux by default still take "excess" RAM and set it up as a cache for the file system?

And finally, Kubuntu 6.10 runs very nicely on my Latitude D820 with 2GB RAM... :D

[bwkaz]

Also, doesn't Linux by default still take "excess" RAM and set it up as a cache for the file system? As long as it can address it, yes (see my earlier reply about caching 2G worth of an NTFS tree ;)).

When I say "as long as it can address it", I mean the whole thing where if you have less than 1G of memory, you have to compile the kernel in one mode (CONFIG_NOHIGHMEM, I think), if you have 1G to 4G of memory, you have to compile in another mode (CONFIG_HIGHMEM_4G), and if you have more than 4G of memory, you have to compile with CONFIG_HIGHMEM_64G. (Or, you just use an x86-64 and a 64-bit kernel. Then you don't care how much memory you have, it's all always accessible, up the the CPU's limit. :p)

[DavidMD]

Greetings, psych-major!FYI - I discovered the hard way that Ubuntu 6.06 had an issue whre it can't boot on a system with more than 2GB memory. I believe this was fixed in 6.10, but I haven't bothered to test it...

Also, doesn't Linux by default still take "excess" RAM and set it up as a cache for the file system?

And finally, Kubuntu 6.10 runs very nicely on my Latitude D820 with 2GB RAM... :DThank you for your contribution to this thread. (I really want to extend the life of my Linux workstation.)

I find it curious that Ubuntu would not boot on a system with more that 2.0-GB of RAM, although I am sure the problem has been fixed.

Perhaps most people running Ubuntu have less than 2.0-GB of RAM, so it took a while for the issue to arise. (How did you realize that RAM was the reason that Ubuntu refused to boot, psych-major?)

My old MSI motherboard will support 2.0-GB of RAM at the most, so I am thinking of "maxing out" the RAM, rather than purchasing a 512-MB PC2100 DIMM. The cost of 512-MB of RAM is about $70, and the cost of 1.0-GB of RAM is approximately $115-$120.

In other words, I could double the RAM without paying twice the cost. ;)

I start a new contract technical-writing job on 12 December (although it could turn into a salaried position with benefits after six months or so). Needless to say, the company, which is a large and international one, is a "Microsoft shop." :( I have not yet asked what tool I will be using for screen shot editing. Perhaps they will let me use The GIMP if they do not have some other tool. :D (I will be the only technical writer in this department, incidentally.)

Anyway... psych-major, at some point I will get paid the first time, and I can consider getting the additional RAM for my Linux workstation. Upgrading the RAM would be my way of celebrating finally getting a job, after months of searching.

No one has yet expressed an opinion as to whether I should go from 1.0-GB to 1.5 or 2.0-GB of RAM. I was using the swap partition with 1.0-GB of RAM, which surprised me.

I would like to "reward" this four-year-old, but totally stable, machine with 2.0-GB of RAM, but I am hoping for some opinions before I spend money on 1.0-GB of RAM instead of 512-MB of RAM.

By the way, psych-major, did you install 2.0-GB of RAM in your Dell Latitude or did you buy it with that much memory? I am curious as to whether or not you made a deliberate decision to run Kubuntu with 2.0-GB of RAM. Thank you! :)

Thanks for your time, psych-major, and everyone!

Cordially,

David

[DavidMD]

Hello, bwkaz.As long as it can address it, yes (see my earlier reply about caching 2G worth of an NTFS tree ;)).

When I say "as long as it can address it", I mean the whole thing where if you have less than 1G of memory, you have to compile the kernel in one mode (CONFIG_NOHIGHMEM, I think), if you have 1G to 4G of memory, you have to compile in another mode (CONFIG_HIGHMEM_4G), and if you have more than 4G of memory, you have to compile with CONFIG_HIGHMEM_64G.... :p)Thank you for your message.

Stupid Question: I have never run Linux with over 1.0-GB of RAM, but if I install a second gigabyte of RAM (2.0-GB, total) after I install Debian "Etch," will I have to do anything special? Will matters be simpler if I install the additional RAM before I install "Etch"?

Thank you very much, bwkaz, for your time, patience, and help! :)

Cordially,

David

[crow2icedearth]

i run 1.5 gigs of ram and have had few problems with the linux kernel. i think that 1 gig of ram is good. if you encode videos i woudl have adleast 1.5 or 2+ gigs.

[psych-major]

Perhaps most people running Ubuntu have less than 2.0-GB of RAM, so it took a while for the issue to arise. (How did you realize that RAM was the reason that Ubuntu refused to boot, psych-major?)

My employer sells a server based product (http://www.virtualtapelibrary.com/dsi9600.html) that has 2 hyper-threaded xeon processors and 4GB RAM. I was trying to boot one with a Ubuntu live CD for some troube-shooting, and it wouldn't boot. I contacted the server vendor, who sells them with CentOS, OpenSuSE or Ubuntu, and he had already seen this effect. There is a workaround, but I stuck with my motto, "Don't forget the problem you're solving." So I left off the Ubuntu and went about it another way.

By the way, psych-major, did you install 2.0-GB of RAM in your Dell Latitude or did you buy it with that much memory? I am curious as to whether or not you made a deliberate decision to run Kubuntu with 2.0-GB of RAM. Thank you! :)
Here (http://www.justlinux.com/forum/showthread.php?t=146992&highlight=dell+sucks) is the story of how I got my beefy new Dell... :D

Thanks for your time, psych-major, and everyone!
Any time!

[sabbathpriest]

Stupid Question: I have never run Linux with over 1.0-GB of RAM, but if I install a second gigabyte of RAM (2.0-GB, total) after I install Debian "Etch," will I have to do anything special? Will matters be simpler if I install the additional RAM before I install "Etch"?

Your system will recognize the new RAM on boot, you don't have to worry about installing it before you change or install your OS.
Cheers! :)

[bwkaz]

if I install a second gigabyte of RAM (2.0-GB, total) after I install Debian "Etch," will I have to do anything special? You will have to ensure the kernel that you choose to install can address all your memory, but if the kernel can address the full first gigabyte, then it can address up to about four, so you should be fine in either case. (The choices are less than 1GB, 1GB to about 4GB, and > about 4GB. I say "about" because memory-mapped I/O takes away from the 4GB number; MMIO devices such as PCI cards have to be given an address block somewhere inside the 4GB range.)

Or just install a 64-bit kernel... but I don't know what kinds of options Debian has for this, so it may not be easy. Heck, it may not even be possible, but considering all the other CPUs that Debian runs on, it should be.

[DavidMD]

Greetings, crow2icedearth!i run 1.5 gigs of ram and have had few problems with the linux kernel. i think that 1 gig of ram is good. if you encode videos i woudl have adleast 1.5 or 2+ gigs.Thank you for your feedback.

I do plan to do video encoding, although I realize my slower Pentium-4 processor will be a "bottleneck." (I hope that I do not have any problems with 2.0-GB of RAM and the 2.6.x kernel that will come standard with Debian "Etch.")

After I begin a new contract technical-writing job on 12 December, and start earning a decent income, I believe that I will go ahead an upgrade to 2.0 GB of RAM.

I want to prolong the life of this computer for as long as possible.

Thank you, again, crow2icedearth! :)

Cordially,

David

[DavidMD]

Hello, psych-major!My employer sells a server based product (http://www.virtualtapelibrary.com/dsi9600.html) that has 2 hyper-threaded xeon processors and 4GB RAM. I was trying to boot one with a Ubuntu live CD for some troube-shooting, and it wouldn't boot. I contacted the server vendor, who sells them with CentOS, OpenSuSE or Ubuntu, and he had already seen this effect. There is a workaround, but I stuck with my motto, "Don't forget the problem you're solving." So I left off the Ubuntu and went about it another way.

Here (http://www.justlinux.com/forum/showthread.php?t=146992&highlight=dell+sucks) is the story of how I got my beefy new Dell... :D

Any time!I enjoyed reading how your got your brand-new, upgraded Dell, although it is always a hassle to return computers -- especially if they get lost!

I assume that you resolved all of the configuration issues that you had when you were installing Linux on the replacement laptop. I would love to have a Linux laptop some day, but right now, I am trying to get the most out of my againg Linux workstation. (I am actually emotionally attached to this machine -- which I know is goofy -- perhaps because I have "gutted" the case and "created a new computer" three times now, although the fourth upgrade will not be financially possible for a while.)

Thank you, again, psych-major, for your help! :)

Cordially,

David

[DavidMD]

Greetings, sabbathpriest!Your system will recognize the new RAM on boot, you don't have to worry about installing it before you change or install your OS.

Cheers! :)Thank you very much for your helpful answer to my very stupid question! :D

I start a new contact technical-writing job on 12 December, but I cannot afford to upgrade to 2.0-GB of RAM (from 1.0-GB) until after I get paid the first time.

Given the fact that I have about a week before I start the position, I am hoping and planning to clean up my computer workstation area, to install a new video card and hard drives in my Linux workstation (hardware that I bought early this year from Newegg.com, when I had some discretionary money), and to do a 'Net install of Debian "testing"/"Etch."

I do not know which iteration of the 2.6 Linux kernel comes with Debian "Etch," but I will try to find out by searching the Debian Web site. My hope is that the 2.6.x kernel that "Etch" uses will natively support 2.0-GB of RAM.

Thank you, again, for your help and warm wishes!

Cordially,

David

[DavidMD]

Greetings, bwkaz!You will have to ensure the kernel that you choose to install can address all your memory, but if the kernel can address the full first gigabyte, then it can address up to about four, so you should be fine in either case. (The choices are less than 1GB, 1GB to about 4GB, and > about 4GB. I say "about" because memory-mapped I/O takes away from the 4GB number; MMIO devices such as PCI cards have to be given an address block somewhere inside the 4GB range.)

Or just install a 64-bit kernel... but I don't know what kinds of options Debian has for this, so it may not be easy. Heck, it may not even be possible, but considering all the other CPUs that Debian runs on, it should be.Thank you very much for your time and reply.

As I stated in a recent, previous reply in this thread, I do not know which iteration of the 2.6.x Linux kernel that Debian "Etch" uses, so I need to find out.

When I ran SuSE Linux on this computer, with 1.0-GB of RAM, SuSE recognized the full amount of RAM, but I will still using the swap partition for some reason.

If the release of SuSE Linux that I was using, which had an older version of the Linux kernel, recognized the gigabyte of RAM, then I assume that Debian "Etch" will recognize 2.0-GB of RAM, because it falls within the "1GB to about 4GB" range that you mention, bwkaz.

I could be extra cautious and not install Debian "Etch" until after I start the new job on 12 December and get paid so that I can afford the additional 1.0-GB DIMM -- to ensure that Debian "Etch" recognizes all 2.0-GB of memory -- or I can use the time that I have this week, before I start the position, and do a 'Net installation of "Etch" -- and hope that Debian recognizes the 2.0-GB of RAM after I purchase and install it. I hope that I am making sense, as I think aloud and record my rambling thoughts! :p

Because I have a four-year-old 2.0-GHz, Pentium-4 processor (without hyperthreading), I assume that I must install the 32-bit kernel, and that the 64-bit, x86 kernel is out of the question.

Please let me know, bwkaz, if I am have a logical "plan of action." I have been told in this thread that I can install Debian "Etch" and then add the 1.0-GB DIMM after I can afford to buy it and it arrives. Thanks! :)

Nothing will change the fact that I built this computer just over four years ago, that it has slow (by today's standards) PC2100 RAM, and that the MSI motherboard has a 2.0-GHz, Pentium-4 processor without hyperthreading.

I am hoping, however, that the additional RAM will help "perk up" the system, keep me from using the swap partition, and allow me to work with video editing. In addition, as I have stated above, I am installing the first 3-D video card that this computer has had (a 4X, 128-MB, ATI Radeon 9250); plus, I am replacing the two older hard drives with two new and larger, 120-GB, Seagate drives.

The motherboard supports RAID and I have used the feature in the past to install a third hard drive on IDE 3, but I do not see the third hard drive as being necessary at this point, nor do I know how "Etch" handles RAID support.

Assuming that I do not encounter kernel problems with Debian "Etch" and the 2.0-GB of RAM (which I will not know until I order and install the 1.0-GB DIMM), the additional RAM, better video card, and larger (faster) hard drives should breathe new life into this computer, especially given Debian's reputation for using system resources efficiently.

I have never installed Debian before, bwkaz, although I did recently download and experiment with what I believe is the Debian project's first "live" CD ISO. I enjoyed the experience, but it obviously was not the same as actually installing, configuring, and running Debian.

After having used SuSE Linux for over four years, I will feel like a neophyte/"newbie" starting with Debian, but I am very excited about the prospect of using Debian!

Thank you, again, bwkaz! :)

Cordially,

David

[psych-major]

Hello, psych-major!I enjoyed reading how your got your brand-new, upgraded Dell, although it is always a hassle to return computers -- especially if they get lost!
It took a fair amount of follow through on my part, but it was definitely worth it in the end!
I assume that you resolved all of the configuration issues that you had when you were installing Linux on the replacement laptop. I would love to have a Linux laptop some day, but right now, I am trying to get the most out of my aging Linux workstation. (I am actually emotionally attached to this machine -- which I know is goofy -- perhaps because I have "gutted" the case and "created a new computer" three times now, although the fourth upgrade will not be financially possible for a while.)
Kubuntu is running very beautifully on the Dell laptop. I have had a couple of hiccups, but nothing beyond minor speed bumps, or issues of my own creation.

As for older machines, I have a PIII at the office that I run as a file server and spare workstation. I maintain Slackware on it, and it just plain runs. Part of the point of Linux is that you can tailor it to the hardware you have, rather than the other way around.

[bwkaz]

I do not know which iteration of the 2.6.x Linux kernel that Debian "Etch" uses, Shouldn't matter. These limits are the same on all of them. :)

I could be extra cautious and not install Debian "Etch" until after I start the new job on 12 December and get paid so that I can afford the additional 1.0-GB DIMM -- to ensure that Debian "Etch" recognizes all 2.0-GB of memory -- or I can use the time that I have this week, before I start the position, and do a 'Net installation of "Etch" -- and hope that Debian recognizes the 2.0-GB of RAM after I purchase and install it. I hope that I am making sense, as I think aloud and record my rambling thoughts! :p Bah, just do the netinstall. ;)

The worst that can happen is it not recognizing more than about 800-some megs of RAM -- in which case all you'll have to do is install a different kernel. (Or compile the kernel yourself. But either way, it's not that hard, and the old kernel will still work until you get a working new one.)

Because I have a four-year-old 2.0-GHz, Pentium-4 processor (without hyperthreading), I assume that I must install the 32-bit kernel, and that the 64-bit, x86 kernel is out of the question. Unfortunately for you, yes. :)

I really like what I get from the x86-64 compared to 32-bit mode: 8 extra general-purpose registers, plus I don't have to worry about memory until I run into the x86-64's 48-bit page tables. (That's 128 terabytes, I believe.)

I have been told in this thread that I can install Debian "Etch" and then add the 1.0-GB DIMM after I can afford to buy it and it arrives. Thanks! Yep, that's correct, you can add it later.

[crow2icedearth]

reetings, crow2icedearth!
Quote:
Originally Posted by crow2icedearth
i run 1.5 gigs of ram and have had few problems with the linux kernel. i think that 1 gig of ram is good. if you encode videos i woudl have adleast 1.5 or 2+ gigs.
Thank you for your feedback.

I do plan to do video encoding, although I realize my slower Pentium-4 processor will be a "bottleneck." (I hope that I do not have any problems with 2.0-GB of RAM and the 2.6.x kernel that will come standard with Debian "Etch.")

After I begin a new contract technical-writing job on 12 December, and start earning a decent income, I believe that I will go ahead an upgrade to 2.0 GB of RAM.

I want to prolong the life of this computer for as long as possible.

Thank you, again, crow2icedearth!

Cordially,

David

no problem. I am not sure if debain has over 1 gig supported in kernel by default. I know that i had to add support when i recompiled my kernel becuase only 1 gig was showing. I noticed it when i ran the free command . I fixed the problem 10 minutes after i noticed it.

[psych-major]

I don't know which version of Debian my Kubuntu build is based on, but I'm running with 2GB memory with no special workarounds required.
(kernel 2.6.17-10-386)

Also, the servers I mentioned earlier this post, though granted they are x86_64, run SuSE 9.3 with 4GB RAM, again with no special workarounds.
(kernel 2.6.11.4-21.7-smp)

[DavidMD]

Hello, bwkaz.Shouldn't matter. These limits are the same on all of them. :)

Bah, just do the netinstall. ;)

The worst that can happen is it not recognizing more than about 800-some megs of RAM -- in which case all you'll have to do is install a different kernel. (Or compile the kernel yourself. But either way, it's not that hard, and the old kernel will still work until you get a working new one.)

Unfortunately for you, yes. :)

I really like what I get from the x86-64 compared to 32-bit mode: 8 extra general-purpose registers, plus I don't have to worry about memory until I run into the x86-64's 48-bit page tables. (That's 128 terabytes, I believe.)

Yep, that's correct, you can add it later.Thank you very much, bwkaz, for your helpful reply.

I knew that there was no way that I could run in 64-bit mode on 32-bit hardware. ;)

I had assumed that I could addition the additional GB of RAM after I installed Debian "Etch," but I just wanted to make certain.

Thank you, again, bwkaz!

Cordially,

David

[DavidMD]

Hello, crow2icedearth.no problem. I am not sure if debain has over 1 gig supported in kernel by default. I know that i had to add support when i recompiled my kernel becuase only 1 gig was showing. I noticed it when i ran the free command . I fixed the problem 10 minutes after i noticed it.Thank you for your message.

I will just have to wait to see if Debian "Etch" supports 2.0-GB of RAM.

If the Debian iteration of the 2.6 kernel does not support memory greater than one gigabyte, then I will have to recompile the kernel -- and I have never recompiled a kernel! :p

Thank you, again, crow2icedearth!

Cordially,

David

[DavidMD]

Greetings, psych-major!I don't know which version of Debian my Kubuntu build is based on, but I'm running with 2GB memory with no special workarounds required.
(kernel 2.6.17-10-386)

Also, the servers I mentioned earlier this post, though granted they are x86_64, run SuSE 9.3 with 4GB RAM, again with no special workarounds.
(kernel 2.6.11.4-21.7-smp)Thank you very much for your message.

I have not had the time yet, but I want to research the Debian Web site to see which iteration of the 2.6 Linux kernel is the default for "Etch," or look for documentation about memory limits. I definitely want support for 2.0-GB of RAM, even if I have to recompile the kernel.

Thank you, again, psych-major! :)

Cordially,

David

[DavidMD]

Hello, psych-major.It took a fair amount of follow through on my part, but it was definitely worth it in the end!

Kubuntu is running very beautifully on the Dell laptop. I have had a couple of hiccups, but nothing beyond minor speed bumps, or issues of my own creation.

As for older machines, I have a PIII at the office that I run as a file server and spare workstation. I maintain Slackware on it, and it just plain runs. Part of the point of Linux is that you can tailor it to the hardware you have, rather than the other way around.It takes effort to make such hardware exchanges, but I am glad that your persistence paid off.

In addition, I am glad that Kubuntu is running well on your Dell laptop. I have known several people where were able to get Linux running on a Dell Latitude, but not an Inspiron.

Thanks!

Cordially,

David

[psych-major]

The inspiron shouldn't be that different, as they are all made for Dell by Acer...

Incidentally, I just this morning noticed that my laptop was using only one of the two cores in my core duo processor. Hmmm...

It turns out that by default my machine was using the 2.6.17-10-386 kernel rather than the 2.6.17-10-generic kernel, with smp support. Hmmm...

I don't know if that's because of something I did, or what, but I noticed in /boot that both kernels were present, so I edited /boot/grub/menu.lst to reference the correct kernel and rebooted.

X refused to start, but I had multi-processor support... The new problem was that my NVIDIA driver was compiled against the other kernel. I changed that to the generic nv driver and I was able to boot and log into KDE, albeit without my docking station.

I went to the package manager and the only nvidia driver there was for the 386 kernel, I bet that's where it came from in the first place, anyway, I went instead to the nvida website and downloaded the latest driver directly.

The nvidia driver needs to be installed with X not running, but unfortunately Ubuntu doesn't seem to have a runlevel like that, except for the recovery mode, which boots into single user mode. I booted to that and ran the nvidia install script, it complained about the runlevel, with the option to continue anyway, so I did.

Next it was unable to find kernel headers and offered to check the ftp site, that's not uncommon and I said OK.

None were found there, so it needed to compile, again not uncommon so I said OK.

As it finished the install, it complained about several directories under /lib that were not present, and it installed to /usr instead. Whatever...OK.

Finally the install finished and I had the choice to automatically configure xorg.conf. I said yes, it worked, I rebooted and now I have both processors, AND my nvidia driver, which I need in order to get the docking station to work.

Phew!!!

[psych-major]

Oh, and it has recognized my 2GB of RAM just fine this whole time. :cool:

[DavidMD]

Hello, psych-major.The inspiron shouldn't be that different, as they are all made for Dell by Acer....Thank you for your message, psych-major.

According to a CTO with whom I worked recently. The Latitude models tend to stay consistent with parts, whereas the Inspiron line uses whatever is the least expensive at the time (to Acer, one assumes), so that parts can vary quite a bit in Inspirons of the very same model.

I am not "basing" Acer, :) but simply stating that, for people with whom I worked early this year, every person was able to install her or his distribution of choice on a Dell Latitude, although not without typical "glitches," such as getting wireless networking to function.

Finally the install finished and I had the choice to automatically configure xorg.conf. I said yes, it worked, I rebooted and now I have both processors, AND my nvidia driver, which I need in order to get the docking station to work....Thank, goodness, psych-major. I wonder why Ubuntu does not have the 'runlevel' option, which I consider standard for Linux?

Congratulations on solving your problem, psych-major! :)

Cordially,

David

[DavidMD]

Hello, again, psych-major.Oh, and it has recognized my 2GB of RAM just fine this whole time. :cool:Thank you for your update and the information.

I will just have to see what happens with Debian 4.0 ("Etch")! ;)

I appreciate your time and help, psych-major! :D

Cordially,

David

[ladoga]

no problem. I am not sure if debain has over 1 gig supported in kernel by default. I know that i had to add support when i recompiled my kernel becuase only 1 gig was showing. I noticed it when i ran the free command . I fixed the problem 10 minutes after i noticed it.
Debian 2.6.x kernels use 4GB max as default, but recompiling new one with support for 64GB is easy if it's needed.

[ladoga]

Hello, again, psych-major.Thank you for your update and the information.

I will just have to see what happens with Debian 4.0 ("Etch")! ;)

I appreciate your time and help, psych-major! :D

Cordially,

David

You have everything set up just fine. More reading without direct experience of things you'll face will just confuse you more. No need to worry about problems that don't exist, eh?

You said that you have P4 CPU so you might want to install i686 kernel at some point. Current in debian Etch is linux-image-2.6.17-2-686.

Also if you suddenly decide to get up to 64GB of RAM there's another package called as linux-image-2.6.17-2-686-bigmem, which is just one apt-get install away. So unless you go for more RAM than that you should be set in few seconds. ;)

[DavidMD]

Greetings, ladoga!Debian 2.6.x kernels use 4GB max as default, but recompiling new one with support for 64GB is easy if it's needed.Thank you very much for your helpful reply.

I now know that I can run Debian "Etch" with 2.0-GB of RAM without having to modify the kernel.

I would love to have a Linux computer that supported more memory, but my self-built PC should easily handle Debian and most distributions, assuming that each distribution is compatible with my workstation's hardware.

Thank you again, ladoga!

Cordially,

David

[DavidMD]

Hello, again, ladoga!You have everything set up just fine. More reading without direct experience of things you'll face will just confuse you more. No need to worry about problems that don't exist, eh?

You said that you have P4 CPU so you might want to install i686 kernel at some point. Current in debian etc is linux-image-2.6.17-2-686.

Also if you suddenly decide to get up to 64GB of RAM there's another package called as linux-image-2.6.17-2-686-bigmem, which is just one apt-get install away. So unless you go for more RAM than that you should be set in few seconds. ;)Thank you for your reply, and you are correct that I should not confuse myself. ;)

ladoga, you write, "Current in debian etc is linux-image-2.6.17-2-686." Is the 'etc' supposed to be "Etch"? If I interpret your paragraph correctly, I need to install the i686 kernel in order to get the best performance out of Debian.

I am a bit confused, however, because I am not sure if the Debian "Etch" kernel is 'linux-image-2.6.17-2-686' -- or that I need to install that kernel in order to benefit the most from my Pentium 4 processor.

If I need to install a new kernel, in order to take full advantage of my Pentium 4 processor, I would like to do so just as soon as I have completed the first step of the 'Net installation of Debian "testing/Etch." I have never modified or recompiled a Linux kernel, so the experience will be good for me, even if the task seems intimidating to me right now. :p

Thank you for all of your time and help, ladoga!

Cordially,

David

P.S. -- Most of my free time until I start a contract technical-writing job on Tuesday (12 December) is already committed, unfortunately. I really would like to get Debian set up before I start the job, because I realize that I will have weekends only to work with Linux.

(The job will be stressful, so -- after work, during the week -- I will basically eat dinner and go to bed on Monday through Friday.) :mad:

[XiaoKJ]

Actually, in debian, the kernel images will work for any version. A kernel for sarge should still work with etch anyway. These are all linux kernels. The difference is only maybe performance and features and API.

[ladoga]

ladoga, you write, "Current in debian etc is linux-image-2.6.17-2-686." Is the 'etc' supposed to be "Etch"? If I interpret your paragraph correctly, I need to install the i686 kernel in order to get the best performance out of Debian.

Right, it was supposed to be Etch. Fixed that now.

If I need to install a new kernel, in order to take full advantage of my Pentium 4 processor, I would like to do so just as soon as I have completed the first step of the 'Net installation of Debian "testing/Etch." I have never modified or recompiled a Linux kernel, so the experience will be good for me, even if the task seems intimidating to me right now.

Yes, installing the correct kernel package will get little more out of your system so it's not bad idea to do. linux-image-686 is a "dummy package" for installing pentium optimized version of the latest Debian Etch stock kernel. I think it also supports symmetric multiprocessing (SMP), which takes advantage of HT in P4 CPUs.

There's nothing intimidating in installing it. Just:
# apt-get install linux-image-686
...in few seconds you'll be all set. Then just reboot to use the new kernel.


I haven't noticed big gains from compling my own kernels that include only support for my hardware and nothing else. Debian stock ones seem to be about equally fast (most of options in them have been compiled as modules and those modules are never loaded unless you have the hardware they support).

Only reasons to compile your own kernel that I can think of:

1. You run into compatibility problems, which cant be solved without removing something/adding something from/to the kernel.

2. Just for fun.

3. You want to save few megabytes of HDD space by not compiling unneeded modules.

4. You are not happy with some options of the default debian kernel and think you know what would fit you better.

I.E. You might want to lower latencies at cost of thoughput if you're a musician and need to have accurate timings when working with MIDI devices. In default debian kernel there's no kernel pre-emption and timer frequency is at 250Hz. In order to get lowest possible latency for the userspace tasks you would want to use full pre-emption and 1000Hz timer freq.

[ladoga]

Once you have booted up using -686 kernel you can safely remove the old kernels and their dummy packages.
dpkg -l | grep 486 might help to spot the right ones.

apt-get --purge remove <package> is similar to dpkg -P <package> in that it will remove the package and leave no associated configuration files or other traces. (plain apt-get remove doesnt touch the config files)

[DavidMD]

Hello, XiaoKJ.

Thank you for your reply.

You state, "Actually, in debian, the kernel images will work for any version.... The difference is only maybe performance and features and API."

Based upon the replies that I have recieved so far, I am hoping that Debian "Etch" will recognize 2.0-GB of RAM. In addition, I do want the performance features (if any).

Thanks again!

Cordially,

David

P.S. -- I hope that you received my PM as an apology in response to your complaints about my long posts and "over-quoting." Again, I am sorry. :(

[DavidMD]

Greetings, ladoga.Right, it was supposed to be Etch. Fixed that now.

Yes, installing the correct kernel package will get little more out of your system so it's not bad idea to do. linux-image-686 is a "dummy package" for installing pentium optimized version of the latest Debian Etch stock kernel. I think it also supports symmetric multiprocessing (SMP), which takes advantage of HT in P4 CPUs.

There's nothing intimidating in installing it. Just:
# apt-get install linux-image-686
...in few seconds you'll be all set. Then just reboot to use the new kernel.....Thank you very much for your helpful message.

I will retrieve the 'linux-image-686' file via 'apt-get', after I have performed the first steps of the 'Net install of Debian "Etch"/"testing" (after rebooting).

Unfortunately for me, my 2.0-GHz Pentium-4 processor does not support hypertheading, and I assume that the same is true of my MSI motherboard. :(

Thank you, again, ladoga! You are always very helpful, courteous, and patient with me, and I am extremely grateful! :)

Cordially,

David

[DavidMD]

Hello, ladoga! :) Once you have booted up using -686 kernel you can safely remove the old kernels and their dummy packages.
dpkg -l | grep 486 might help to spot the right ones.

apt-get --purge remove <package> is similar to dpkg -P <package> in that it will remove the package and leave no associated configuration files or other traces. (plain apt-get remove doesnt touch the config files)Thank you for your helpful reply, ladoga.

I assume that I find the old kernels using 'dpkg -l | grep 486' and then use 'apt-get --purge remove <package>' to remove the old kernels?

Thank you, again! :)

Cordially,

David

[ladoga]

Yes, dpkg -l will list all the packages on your system and grep 486 piped after that filters out everything that does not contain 486.

So it will look something like this:


$ dpkg -l | grep 486
ii linux-image-2.6-486 2.6.17+2
ii linux-image-2.6.17-2-486 2.6.17-9
ii linux-image-486 2.6.17+2

Then to remove these packages:
# apt-get --purge remove linux-image-486 linux-image-2.6-486 linux-image-2.6.17-2-486

Reason there is three different packages for the same kernel is that two of them are "dummies".

So for example:
Installing dummy package linux-image-486 installs the lastest -486 compatible kernel.
Installing dummy package linux-image-2.6-486 installs the lastest -486 compatible kernel from the 2.6 branch.

Both will currently do the same as 2.6 is the latest branch, but in case 2.8 kernel branch existed installing linux-image-486 would choose latest kernel from it, while linux-image-2.6-486 would install the latest one from 2.6.

This is useful for controlling upgrade strategy with apt. If one installs linux-image-2.6.17-2-486, which is the actual kernel package, it will not upgrade even if a newer kernel is around. (the new package is named differently IE. linux-image-2.6.18-486).

If one installs dummy package linux-image-2.6-486 then the kernel will be upgraded whenever newer one is around as the linux-image-2.6-486 always depends on latest 2.6 kernel available.

We are getting off-topic aren't we? :)

[XiaoKJ]

Unfortunately for me, my 2.0-GHz Pentium-4 processor does not support hypertheading, and I assume that the same is true of my MSI motherboard. :(
Well, david, IIRC, that does not matter. I've got the impression that SMP kernels will just be a little slower and a little bigger than non-SMP kernels and should still run on non-SMP machines (that do not have hyperthreading or multi core or multi processors)

I'm not very sure though, but if you are up and running with the new kernel, then I'm right.

Secondly, in the my post above, I really do mean that any linux kernel should run in any linux system. Even if I use my Gentoo kernel in Ubuntu. Don't get confused over my horrible English...

And since i'm already here, I'd like to add that, after changing kernels, you should test out them before removing the old one. This is for safety. By testing, I mean running your usual applications to see if they still work right. For example, in windows-land, if you upgraded to XP SP2, some things won't work anymore, because they changed something in the kernel. These irksome events will surely happen given enough upgrades, so safety is best.

[DavidMD]

Hello, ladoga!

Thank you for your message.

I see now that it is relatively simple to remove the '486 kernels and then run the command, 'apt-get install linux-image-686', to install the '686 kernel.

I assume that I can upgrade the '686 kernel the same way that I update other Debian packages? (Thanks!)

I guess the only risk that I run is if the '686 kernel has problems, because I will have removed the '486 kernels.

If I do not remove the '486 kernels until after I have confirmed that everything works correctly with the '686 kernel, I assume that I first need to back up these earler kernels in such a way that Debian will use the '686 kernel? I hope that I am correct that I should take this precaution, ladoga. :confused:

I apologize for the additional questions. :o I realize that "Linux is the kernel," however, and that I could create a huge mess if I am not careful. ;)

Thank you, ladoga!

Cordially,

David

[DavidMD]

Greetings, XiaoKJ!

Thank you for your information about using SMP kernels.

The first time that I installed SuSE Linux Professional over four years ago, I accidentally selected the SMP kernel option during the installation. I had numerous problems (none of which I can recall, unfortunately), so I reinstalled SuSE with a single-processor kernel and the problems all went away.
And since i'm already here, I'd like to add that, after changing kernels, you should test out them before removing the old one. This is for safety. By testing, I mean running your usual applications to see if they still work right. For example, in windows-land, if you upgraded to XP SP2, some things won't work anymore, because they changed something in the kernel. These irksome events will surely happen given enough upgrades, so safety is best.Thank you for this prudent advice.

I remember that one update for Windows XP Service Pack 2 "broke" Windows for people running a certain Hewlett-Packard scanning utility.

Because I have always used the kernel that came with SuSE Linux, I have not dealt at all with installing a new kernel, which I want to do with Debian "Etch." I love Linux, but it is interesting how often I feel like a neophyte/"newbie" again! ;)

If I do not delete the '486 ("old") kernels, will Debian automatically use the '686 ("new") kernel after I install it with apt-get and then reboot?

As you say, I can then test to see if the new kernel has not adversely affected Debian "Etch" and then delete the '486 kernels, or back them up.

Thank you, again, XiaoKJ! :)

Cordially,

David

[XiaoKJ]

David, kernels in debian management is designed after some common sense. I mean that, right after installing a new kernel (686 is your case), the installer will pick the new kernel and make it default. Its only rational to do so, since people install the new kernel to use them.

In linux land, changing kernels is very common. So, the kernels are built such that each version is separated from the other versions. In simple terms, installing kernel a will not affect kernel b in any possible way. After installing the new kernel, the old kernel should work the same way. Grub may now pick the new kernel as default, but it is simple to change back to the old kernel at start-up by choosing the old kernel before the timer.

In fact, this design is so robust that there isn't the need to back up kernels. Nice?
In debian, the kernel can be kept in a deb file for other computers to install. It can also serve as a back up, for your info.

Finally, in debian, the 686 kernel can be updated the same way you update the 486 kernel, yadayada. As long as debian maintainers want to release them, it can be updated by the apt-get system. And the kernels aren't so different anyway, just optimised for different version of the x86 architecture.

Therefore, david, if the 686 kernel runs fine, just feel free to purge the 486 kernel. There is definitely no need to do the backing up anyway. I, for one, keep only 1 kernel on my systems, and simply copy the compiled kernel for 1 machine to the others (which can also serve as back up)

[DavidMD]

Hello, XiaoKJ!David, kernels in debian management is designed after some common sense. I mean that, right after installing a new kernel (686 is your case), the installer will pick the new kernel and make it default. Its only rational to do so, since people install the new kernel to use them....Thank you very much for your helpful and informative reply.

I will install the '686 kernel package and leave the '486 kernel(s) until I am certain that all is well. :)

Again, thank you, XiaoKJ.

Cordially,

David