2012-12-30

Migrate /home in Ubuntu

Sadly Ubuntu does not have LVM enabled in the default install, as this whole issue would be solved with a simple pvmigrate and lvresize...

My /home (which is on a separate /dev/sda5 partition) is filling up.
The availability of Steam on Linux gave it the final blow: it's time to bring in another partition.
As I don't want to commit a whole partition to /home, I've mounted /dev/sdc2 as /space and I'm going to create a symlink to an home subdirectory.

First, boot Ubuntu in rescue mode and select root shell.

Mount all filesystems

#mount -a

note that mounted filesystem won't be visible with a df, but you should cat /proc/mounts to see them
Set proper permission to the new partition

#chown root:root /space
#chmod 755 /space

Then create the new home and copy the old one

#mkdir /space/home
#cp -a /home/* /space/home/

Mount / read/write as we'll need to modify the fstab

#mount / -o rw,remount
#vi /etc/fstab

Comment the old /home
Remove the old home mount point and create the new symlink

#umount /home
#rmdir /home
#ls -s /space/home /home

Reboot

A trip by the sea

Having survived Christmas and its endless lunches and dinners, a change of pace was necessary: so we decided for a walk near the sea.
From home, it's a 75+75km trip.

Here is the elevation profile of the road: it starts at 97m, goes up to 590m and down to 10m


On the downward slope, I was caught in a traffic jam: 15 minutes of stop-and-go slow moving.
Here is a snapshot, 9 minutes in the jam: not only I didn't use the engine at all, but I even charged the battery.


That's a fully charged battery, a rare sighting in normal traffic:


Back home, the total mileage was 5.0 l/100Km
I'll compare this result with a later summer trip, where temperatures will be more favorable to better mileage and the car will have more running (it only has 2500Km right now).

2012-12-17

B


According to the manual, the B gear should be used on slopes to slow down the car without stressing the brakes.
Some people say that B gives a better grip on snowy roads, even on flat ones.
Since we had snow a couple of days ago, I've done some tests.
No hills here, so just flat, icy roads.
The B allows you to slow down approaching crossroads without touching the brakes: it may somewhat confuse the drivers that follow.
Anyway, while driving with the B on, and cruising at constant speed, I noticed an higher noise level than usual: the engine was running at high RPM rate.
At 68 km/h instant mileage was 6.2 l/100km
Shifting back to the D gear lowered consumption back to 5.0 - 5.2 l/100km.
I asked some Prius and Auris drivers, and it seems in those cars, driving in B, on a plain road, is just the same as driving in D, with no different RPM rates.
Is this a different behavior of the Yaris Hybrid?

2012-12-12

Women and Engines revisited?

This used to be an authoritative site for PC enthusiast.
Then, it began publishing photos of winking girls posing with PC hardware as in
http://www.tomshardware.com/picturestory/614-gift-guide-technology-recommendation.html
Is it just the evolution of the old "women and engines"?

2012-12-04

The Reboot Syndrome

Shouldn't reboots be an exclusive feature of Windows-based OSes?
It doesn't seem so.
This morning, while driving, I turned on my Yaris infotainment system with the MODE button on the steering wheel.
It turned on as usual with the FM station tuned in. (Bad design here: it was on the USB player when I turned it off yesterday)
I pressed MODE again to switch to USB and bang!


The screen showed the Hybrid logo of the boot sequence.
After that, it correctly switched to USB.

Note:
QNX should be a crash resistant OS, able to reload only the offending module.
Reboot was really fast, barely the time to think "what's that?" and the system was back on line: however it's not an excuse...

2012-12-01

Attack of the QWERTY Androids

Android phones with full QWERTY physical keyboards are virtually non-existent.
Samsung has one low-spec phone targeted at the young chat addicted, HTC has none, the last Motorola is the years-old Droid.
No interesting phones in sight either.
As more and more businesses are ditching Blackberry as Yahoo in http://www.pcmag.com/article2/0,2817,2409780,00.asp, someone in charge will finally realize that doing serious email work on a touch keyboard is false promise.
Will we see more QWERTY Android phones in the near future?