Wednesday, December 26, 2012

how to disable annoying Super Key in Ubuntu Linux with Unity Window Manager

First I should say that Super brings up the big overlay grid, that is called the Dash. Tappipng Alt brings up the HUD, a smaller text field in the top left. It's a 'type-a-little' interface to all the commands in system and application menus. We can get a link for more info, if needed.
So you can shut off the Super key, with the low-level tool Compiz Config Settings Manager. The package name is compizconfig-settings-manager, if it's not installed yet.
Open the Dash, and type 'ccsm'. You should see an icon you can run. When the app opens, you may get a warning that it's a tool that can mess up your system. This is true; it doesn't have any constraints on choosing settings that may break your desktop in different ways. But this change alone will be ok.
In CCSM, find and choose 'Ubuntu Unity Plugin'. The first tab, Behavior, should have an item 'Key to show the launcher'. Click on the button that shows Super, and you can disable it, or choose a different key if you want to try that.
Notes:
- this is how it looks for me under 12.10. It's about the same, as I recall, under 12.04.
- It should probably say 'Key to show the dash'. Maybe I'll find or file a bug about that.
- unchecking 'Enable Ubuntu Unity Plugin', under Unity, is the kind of thing that would send your window controls, and lots of the UI, into never-never land.


Reference


Wednesday, December 19, 2012

harddisk ของ Western Digital มีปัญหากับ RAID-1

หากท่านนำ harddisk ของ Western Digital มาใส่เป็น member ของ RAID-1 ท่านจะพบปัญหาการ rebuild ไม่จบ โดย status ของ raid เมื่อดูด้วย mdadm จะเป็น clean, degraded และ spare rebuilding

สาเหตุเกิดจาก module NCQ ใน harddisk ท่านต้อง disable ที่ sysctl.conf เพิ่มบรรทัด (สมมติ harddisk ลูกนั้นคือ /dev/sdb):

block/sdb/device/queue_depth=1


References

swap file

You can use file as swap space.

dd if=/dev/zero of=/var/swap bs=1M count=10240
mkswap swap
swapon /var/swap
chmod 0600 swap


Add this into /etc/fstab

/var/swap       swap    swap    defaults        0 0