How to Decrease/Speed Up Ubuntu Booting Time

As heard before, Ubuntu has a faster boot time than Windows or Mac, but some users have had a different experience than others. This aim of this article is to explain about it , how it happens and how to make it faster. (thanks to Neil_m)

One factor that influence booting time is a hardware specs, not only about capacity, but whether is the hardware having a good drivers and well supported by Ubuntu. When we boot up the machine, Grub does search for all the necessary drivers to load, this action actually takes a time, a long booting time usually caused by grub does not 'immediately' find the required drivers or some error occurs when the Grub try find that drivers.

One of the ways that help us to speed up ubuntu boot time is removing unnecessary services and drivers that are loaded at boot time. Something that you have to do is tell the Grub to make a new profile. Profile is Grub option that should add to grub configuration file (/etc/default/grub) to inform the boot loader to create a new profile during the next boot loading sequence.

Speed Up Ubuntu Booting Time via Grub
here's to do it, open your grub configuration file (/etc/default/grub) and find this line GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash”, do as follows :

• sudo gedit /etc/default/grub
• replace GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash” with GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash profile”.
• save and exit
• sudo update-grub2
• sudo reboot

Grub does a search for all the necessary drivers to load, Instead of making Grub search for required drivers, the profiling actually makes Grub remember every necessary driver to work, This action will cutting down all of the driver load times. 

after your system up, edit /etc/default/grub and remove some option  which we have added before.

• sudo gedit /etc/default/grub
• replace GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash profile” with GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash”.
• save and exit
• sudo update-grub2

(Other) Using All CPU Cores During Booting
If you have a multi-core CPU/Processor, this following steps may be able to speed up your boot time besides of using the step above, follow these instructions:

• sudo gedit /etc/init.d/rc
• find this line : CONCURRENCY=none or CONCURRENCY=makefile
• replace with : CONCURRENCY=shell
• save and exit

at least my booting time increased by 7 Sec than before, what about you ?

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