Slow 12.04 on a Netbook with LVMs

[Liam Proven]

On 24 April 2013 18:35, Amichai Rotman <amichai at iglu.org.il> wrote:
> Hello,
>
> I have an Asus EeePC running 12.04.2 set up with 3 Pencrypted partitions:
>
> One for the / (System); One for swap and one for /home
>
> The system becomes slower and slower. I noticed that the encrypted
> partitions are set up as extended (=not primary). I read somewhere that that
> slows down the file access.

Do not worry. Primary/secondary imposes no measurable performance
change - nor does position on disk, contrary to what some people will
tell you. I've tried and tested it; it makes no difference consistent
to the 2nd decimal place of a percentage. That is no difference at
all, it's within measurement and experimental error.

What /will/ slow the machine down drastically is encryption!

Consider just encrypting /home. The stuff in the other partitions has
little that is traceable and it is hard to find.

> I want to redo the installation, and I have a few questions:
>
> Can I use an external hard drive formatted as NTFS to backup the files on
> /home (ext4)?

No, not AFAIK.

> I want to create only primary type partitions, I remember that it asks for
> an extended type partition when configuring the encryption.

Don't. The "correct" was is 1 primary + all the others as logicals
inside an extended partition. Make / the primary and /home and swap
the logicals.

> I'd like to create the swap space as a file, not a partition.

Possible but saps performance (marginally, in theory; allegedly Linux
>=2.6 ameliorates this).

If you have 1-2GB of RAM, try zRam and no swap at all. Works well for me.

http://askubuntu.com/questions/174579/how-do-i-use-zram

(The 2nd and 4th answers work and are the easiest.)

> It's a 160Gb SATA drive. I need as much space as possible for my Data files.
> What would be the best way to partition the drive?

How much RAM do you have? If you have >1GB you could possibly do
without swap; if you have >2GB you almost certainly could.

I would use:

primary, 8GB, for /
Extended for all the rest
Inside that, (all the available space - (RAM × 2) as /home, encrypted
if you feel you need to), and at the end, (2×RAM as swap). That gives
you plenty of space for hibernation support.


> What's the best way to configure the LVMs?

LVM? Don't. With a single disk, you don't need it.

--
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