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Enjam
Asked: 2019-01-11 02:46:35 +0800 CST

bcache for Intel Optane on ubuntu

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I would like to use the Intel Optane memory (16GB) with ubuntu 18.10. My Laptop has an HDD for the OS and i thought i can use bcache for this purpose to speed up the experience. Can someone help me how to set it up? The computer has only ubuntu 18.10 on it so there should be no conflict with other os. If my idea is wrong anyone has any better idea on how to use Intel Optane with ubuntu? Thank you very much for the answer!

Bests

dell intel bcache

1 Answers

  1. Best Answer

    I made it work as follows:

    setting AHCI mode in BIOS then i followed the instructions in the following link:

    https://www.kloppenborg.net/blog/2017/11/05/installing-ubuntu-17-10-with-bcache

    If the link is not working, here are the details:

    Overview Before we get going, not that this is only valid for a new installation of Linux as we delete all file system information. If this isn’t what you want to do, I suggest you check out flashcache or EnhanceIO which will let you migrate a live system.

    Here are the major steps:

    Boot the Ubuntu installer Create a partitions for /boot, the backing, and cache devices. Create the bcache device Install Ubuntu onto /dev/bcache0 While still in the live CD, chroot into the new installation Install bcache-tools and re-generate initramfs Reboot into a fully functional system. Properly acknowledging my sources, there are two critical posts on StackOverflow that made me think I could get away with this scheme: alex’s answer on how to setup bcache and Lekensteyn’s answer on how to restore kernels Lastly, be aware that Grub (and Grub2) do not support bcache, so you will need a separate /boot partition.

    Partitioning First, if you have used this system for anything important, back up your data. We’ll be erasing everything shortly.

    Now, boot into the Ubuntu installer and remove any unnecessary partitions. You can use fdisk on the command line or the gparted GUI for this. Now, lets assume that your SSD is /dev/sda and your hard disk is /dev/sdb. Create the following partitioning scheme:

    /dev/sda1 - 1024 MB, EXT4, used for /boot /dev/sda2 - any format, for cache /dev/sdb1 - EFI partition (if your machine needs it) /dev/sdb2 - swap /dev/sdb3 - any format, backing partition

    Don’t worry about doing a deep format of the caching and backing partitions as we’ll wipe these shortly. If you made any major changes to the partition tables, you might need to reboot before you can proceed. gparted, in particular, will let you know if this is the case.

    Loading bcache, creating device First, connect to the Internet. Make sure the connection is working. Next open up a terminal and wipe the cache and backing partition file systems:

    sudo wipefs -a /dev/sda2 sudo wipefs -a /dev/sdb3

    Next we will install bcache-tools and create the bcache device.

    sudo apt-get update sudo apt-get install bcache-tools sudo make-bcache -B /dev/sdb3 -C /dev/sda2 sudo mkfs.ext4 /dev/bcache0

    Notice the command to make-bcache used the HDD partition, /dev/sdb3, as the backing (-B) device and the SDD partition, /dev/sda2, as the cache (-C) device.

    Installing Ubuntu WITHOUT rebooting, run the Ubuntu installer from the desktop. When you get to the installation type screen which lets you pick how to install the OS (e.g. the page that says “Erase disk and install Ubuntu” or “Something else”) choose to do custom partitioning.

    In the partitioning dialog configure the following:

    /dev/bcache0 - format EXT4, use as / /dev/sda1 - format EXT4, use as /boot /dev/sdb1 - EFI partition (if your machine needs it) /dev/sdb2 - swap

    Proceed with the installation as normal. When it completes DO NOT REBOOT as the initramfs installed by the live CD does not have the bcache kernel module. If you accidentally rebooted, simply go back in to the live image, install the bcache-tools package as described above and continue with the instructions below.

    Installing bcache on the new installation Here is where things get tricky. What we’re going to do is switch to the new operating system without booting and install some software to get bcache-tools installed and a new initramfs generated so the computer will boot.

    First we are going to create a valid chroot environment. We start by mounting several directories from the new installation into specific subdirectories in order to create the directory structure Ubuntu Linux expects:

    sudo mount /dev/bcache0 /mnt sudo mount /dev/sda1 /mnt/boot sudo mount --bind /dev /mnt/dev sudo mount --bind /proc /mnt/proc sudo mount --bind /sys /mnt/sys

    Because we will need Internet access, we need to copy the DNS configuration from the live CD into the chroot environment:

    sudo cp /etc/resolv.conf /mnt/etc/resolv.conf

    Next we put ourselves into the chroot:

    sudo chroot /mnt

    Now we are effectively within the new installation’s file system. So all we need to do is install bcache-tools

    sudo apt-get update sudo apt-get install bcache-tools

    After the package is installed, you should notice that the initramfs is re-generated and installed. You can check the timestamps on the files in /boot against date to confirm this is the case.

    Now we clean up. Exit the chroot, cleanly dismount the file system, and reboot:

    exit sudo umount /mnt/sys sudo umount /mnt/proc sudo umount /mnt/dev sudo umount /mnt/boot sudo umount /mnt sudo reboot

    Post-install Restore the default resolv.conf configuration

    sudo ln -s /run/systemd/resolve/stub-resolv.conf /etc/resolv.conf

    With any luck, your machine will reboot normally and you will have a fully functional Ubuntu installation with bcache out of the box without all the work of previous methods.

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