Baslinux mailing list

[sindi keesan <keesan AT sdf.lonestar.org>]

On Mon, 13 Dec 2004 3aoo-cvfd AT dea.spamcon.org wrote:

> sindi keesan wrote:
> > The second RAMdisk is only 2.5MB.
>
> The default BL3 filesystem is around 5mb, so two
> 4mb ramdisks was unnecessary.
>
> > Free -
> > Total memory:   7032K
> > Used:           6088K
> > Free:            944K
> >
> > This implies the BL3 kernel uses about 1MB RAM and the
> > two RAMDISKs and the 'free' program use 6MB RAM, right?
>
> No, the kernel and foundation processes take around 3mb.
> The other 3mb is probably occupied by ramdisks (it appears
> that your empty ramdisk is occupying very little ram).

So a 4MB ramdisk with 2MB files on it, plus an empty 2.5MB ramdisk, 
together occupy only 3MB space?  If I fill the 4MB RAMdisk with files, and 
have 3M of kernel and processes, and delete the other RAMdisk, this should 
still leave about 1MB free RAM to work in.   So it sounds like it will 
produce more usable RAM if I delete anything not being used from the 
RAMdisk - such as X and manpages - in order to make things run a bit 
faster in this tight situation.  Or does removing files from a ramdisk not 
maked it use less ram?

> > /dev/ram0 - 4005K of which 2060 available and 51% used
> > /dev/ram1 = 2515K of which 2502 available and 13 used (/usr/X11R6)
> > This implies that the two RAMDISKS use 6.5MB RAM.
>
> Yes, but the kernel has some ability to use unoccupied
> ramdisk space for working ram.  As you fill the ramdisk
> (eg by loading the second floppy) free ram will probably
> decrease.

I did not know a kernel could use ramdisk as working ram.  Interesting.

I will try loading just disk1, remove the man pages and anything X/games 
(and setleds), then copy over links from a floppy disk and see how it 
works.  I might try timing it before and after deleting X files.  Is there 
anything else I can do to check how much ram is actually usable by the 
kernel?

Our 2400 bps pcmcia modem in a faster 486 was able to make a connection to 
the ISP.  The 2400 bps internal modem in this slower 486 was not (I tried 
three times).  Why?  Does the computer speed affect this?  They are both 
UART --450 not 550A.  The internal one dialed pulse, the pcmcia tone.

I will plug in the external modem to try links.  The computer still needs 
a few screws but is usable for experiments.