Alternate install CD very much slower than installation from live CD

[Carsten Agger]

Binary package hint: ubiquity

I did an OEM mode installation on an MSI Wind U135 using a USB stick with the alternate CD, created using the USB creating tool in System/Administration.

The OEM mode/non-graphical installation took one hour and twenty minutes.

Later, I tried doing an OEM install from the Live CD. This usually takes between fifteen and twenty minutes.

Conclusion: The alternate installation is doing something differently from the live installer, presumably something wrong.

To reproduce:

Download Ubuntu 10.04 live CD and alternate CD.

Put alternate CD on USB key, boot and install on computer in OEM mode. Note that this takes a looong time.

Now put live CD on the same USB key, boot and install on same computer in OEM mode. Note that this is very fast.

[Colin Watson (cjwatson)]

This is inevitable due to the way the alternate install CD works; constructing the installed system by installing packages one at a time is much slower than constructing it by copying over a filesystem tree, but also significantly more flexible. We ship both because of this trade-off.

See also:

  https://wiki.ubuntu.com/LucidLynx/ReleaseNotes#Performance%20regressions%20with%20ext4%20under%20certain%20workloads

... and there's a separate bug about that, but even if this particular issue were fixed then the alternate installer would still be inevitably slower, hence the "Won't Fix".