FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Debian > Debian User

 
 
LinkBack Thread Tools
 
Old 02-01-2009, 04:19 AM
Ron Johnson
 
Default Use of Swap Space

On 01/31/2009 11:01 PM, David Fox wrote:
[snip]


It isn't that RAM has a FAT - those things only are present on
filesystems. It is more likely that free's interpretation doesn't
include kernel memory. Also, 4gb may be 4*1024*1024 not 4*1000*1000,
although that is more likely to be a concern with hard disk capacity.


No, RAM is always measured in binary.

--
Ron Johnson, Jr.
Jefferson LA USA

"I am not surprised, for we live long and are celebrated poopers."


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-01-2009, 03:04 PM
"Mirko Scurk"
 
Default Use of Swap Space

Ron Johnson wrote:
> On 01/31/2009 03:27 PM, Nuno MagalhĂŁes wrote:
>>> Try to run `free' to get a more detailed break up (or even "cat
>>> /proc/meminfo").
>>
>> Running free -g on my system returns 3. I have 4.
>> Running cat /proc/meminfo returns 4030668KB, which is 3.84GB according
>
> That's 4030668*1024 = 4,127,404,032.
>
>> to onlineconversion, closer. Does RAM also have a sort of FAT?
>
> 4GB = 4,294,967,296.
>
> So, where's the missing 167,563,264 bytes? (I.e. 40,909 4KB pages.)
>
>> It seems as though free won't return the accurate size.
>
> Of course it does. "We", though, aren't kernel hackers or h/w
> gurus, so are left in the dark.
>
> --
> Ron Johnson, Jr.
> Jefferson LA USA
>

Could it be that 32-bit Debian can't access rest of memory?

--
Mirko Scurk


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-01-2009, 07:25 PM
Ron Johnson
 
Default Use of Swap Space

On 02/01/2009 10:04 AM, Mirko Scurk wrote:
[snip]


Could it be that 32-bit Debian can't access rest of memory?



That would only be an issue if he could only see (I think) 2GB of
his 4GB RAM.


--
Ron Johnson, Jr.
Jefferson LA USA

"I am not surprised, for we live long and are celebrated poopers."


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-01-2009, 07:49 PM
Lee Glidewell
 
Default Use of Swap Space

On Saturday 31 January 2009 21:01:14 David Fox wrote:
>
> It isn't that RAM has a FAT - those things only are present on
> filesystems. It is more likely that free's interpretation doesn't
> include kernel memory. Also, 4gb may be 4*1024*1024 not 4*1000*1000,
> although that is more likely to be a concern with hard disk capacity.

No, the issue is that manufactures advertise in *1000, while computers use
bytes in *1024. The recent convention that's come into place to represent this
is between Kilo/Mega/Giga-bytes (*1000) and Kibi/Mebi/Gibi-bytes (*1024).

So a stick of memory advertised as 4 Gigabytes is going to present itself to
your computer as 3.84 Gibibytes, roughly.

http://xkcd.com/394/

Lee


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-02-2009, 12:04 AM
Nuno Magalhes
 
Default Use of Swap Space

> So a stick of memory advertised as 4 Gigabytes is going to present itself to
> your computer as 3.84 Gibibytes, roughly.

Er... what's the standard in Debian? 1024, right? We're still being
logical here, right?


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-02-2009, 12:16 AM
Lee Glidewell
 
Default Use of Swap Space

On Sunday 01 February 2009 17:04:38 Nuno Magalhes wrote:
> > So a stick of memory advertised as 4 Gigabytes is going to present itself
> > to your computer as 3.84 Gibibytes, roughly.
>
> Er... what's the standard in Debian? 1024, right? We're still being
> logical here, right?

Sorry, it's more like 3.72 Gibibytes.

Anyway, it has nothing to do with Debian. It has to do with the fact that
computers are binary, and memory manufacturers advertise their products by
measuring in multiples of 10. Some might say that practice is dishonest, but
it is also universal at this point.

And the Kibibyte/Mebibyte/Gibibyte nomenclature was introduced by the IEEE
like 10 years ago, so people really should be familiar with it by now.
 
Old 02-02-2009, 12:59 AM
Ron Johnson
 
Default Use of Swap Space

On 02/01/2009 02:49 PM, Lee Glidewell wrote:

On Saturday 31 January 2009 21:01:14 David Fox wrote:

It isn't that RAM has a FAT - those things only are present on
filesystems. It is more likely that free's interpretation doesn't
include kernel memory. Also, 4gb may be 4*1024*1024 not 4*1000*1000,
although that is more likely to be a concern with hard disk capacity.


No, the issue is that manufactures advertise in *1000, while computers use


Hard drive manufacturers, not RAM manufacturers.

My beard's grey enough to remember when drive manufacturers measured
drive capacity in binary KB, not decimal.


bytes in *1024. The recent convention that's come into place to represent this
is between Kilo/Mega/Giga-bytes (*1000) and Kibi/Mebi/Gibi-bytes (*1024).

So a stick of memory advertised as 4 Gigabytes is going to present itself to
your computer as 3.84 Gibibytes, roughly.


If that were true, I'd have 8 * 10^9 bytes of RAM, and this
demonstrates that error:


$ calc 8 * 10**9 / 1024
7812500

$ cat /proc/meminfo | grep MemTot
MemTotal: 8177796 kB

$ calc 8177796 * 1024
8374063104

$ calc 2**30 * 8
8589934592

The only issue is that I'm "missing" 215871488 bytes (52703 of 4KB
pages).



http://xkcd.com/394/


But seriously: KB was always the standard way of writing kilobyte.
Kb was/is kilobit (now, Mb and Gb are relevant), used my memory
manufactures to indicate the capacity of individual *chips* (not the
SIMMs on which they are mounted).


--
Ron Johnson, Jr.
Jefferson LA USA

"I am not surprised, for we live long and are celebrated poopers."


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-02-2009, 01:15 AM
Lee Glidewell
 
Default Use of Swap Space

On Sunday 01 February 2009 17:59:07 Ron Johnson wrote:
> On 02/01/2009 02:49 PM, Lee Glidewell wrote:
> >
> > No, the issue is that manufactures advertise in *1000, while computers
> > use
>
> Hard drive manufacturers, not RAM manufacturers.
>
> My beard's grey enough to remember when drive manufacturers measured
> drive capacity in binary KB, not decimal.
>
> > bytes in *1024. The recent convention that's come into place to represent
> > this is between Kilo/Mega/Giga-bytes (*1000) and Kibi/Mebi/Gibi-bytes
> > (*1024).
> >
> > So a stick of memory advertised as 4 Gigabytes is going to present itself
> > to your computer as 3.84 Gibibytes, roughly.
>
> If that were true, I'd have 8 * 10^9 bytes of RAM, and this
> demonstrates that error:
> <snipped work>

Okay, I stand corrected. I guess I had assumed that RAM was sold this way as
well, and hadn't bothered to do the math to check it.

You know what they say about people who assume.

I'll go stand in the corner now.

Lee


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-02-2009, 01:51 AM
Ron Johnson
 
Default Use of Swap Space

On 02/01/2009 08:15 PM, Lee Glidewell wrote:
[snip]


You know what they say about people who assume.

I'll go stand in the corner now.


With your nose pressed into the corner, touching that dust spot at
eye level.


--
Ron Johnson, Jr.
Jefferson LA USA

"I am not surprised, for we live long and are celebrated poopers."


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 
Old 02-02-2009, 04:34 PM
"Douglas A. Tutty"
 
Default Use of Swap Space

On Fri, Jan 30, 2009 at 10:04:19PM -0600, Ron Johnson wrote:
> On 01/30/2009 09:54 PM, Douglas A. Tutty wrote:
> >On Sat, Jan 31, 2009 at 02:52:34AM +0000, Tzafrir Cohen wrote:
> >>On Sat, Jan 31, 2009 at 12:54:34AM +0000, Dean Chester wrote:

> >>If a 100% CPU usage causes your computer to *over*heat (which is
> >>something you did not write above) you'll have a problem elsewhere (e.g.
> >>a dist-upgrade that includes tex-live :-) )
> >
> >Or, is the board firmware slowing down the CPU to allow it to cool,
> >which makes a basically idling debian system to use a higher percentage
> >of available CPU (less idle time). Remember, its a percentage of CPU
> >capacity. If the CPU slows down, the the available capacity decreases.
>
> But "100% CPU usage" isn't the same as "running at 100% of rated
> clock speed".
>
> Is *that* what you are really referring to?

To illustrate what I mean, lets change from percentage to some
ficticuous numbers. Lets say that the CPU when cool can make 100
BIGMACS per second. When the CPU is cool, top shows that it is 99% idle
(1% CPU usage), so it takes 1 BIGMACS per second to keep the system and
top running. Now, heat up the CPU too far and the BIOS slows down the
CPU to make it run cooler. Now the CPU can only make 1 BIGMACS per
second. It still takes 1 BIGMACS per second to keep the system and top
running, so now top will show that the CPU is 0% idle (100% CPU usage).

This is what I was suggesting.

Doug.


--
To UNSUBSCRIBE, email to debian-user-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
 

Thread Tools




All times are GMT. The time now is 09:45 PM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org