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On Sat, February 22, 2014 06:27, Facundo Curti wrote: |
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> Hi all. I'm new in the list, this is my third message :) |
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> First at all, I need to say sorry if my english is not perfect. I speak |
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> spanish. I post here because gentoo-user-es it's middle dead, and it's a |
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> great chance to practice my english :) Now, the problem. |
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First of all, there are plenty of people here who don't have English as a |
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native language. Usually we manage. :) |
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> I'm going to get a new PC with a disc SSD 120GB and another HDD of 1TB. |
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> But in a coming future, I want to add 2 or more disks SSD. |
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> |
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> Mi idea now, is: |
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> |
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> Disk HHD: /dev/sda |
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> /dev/sda1 26GB |
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> /dev/sda2 90GB |
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> /dev/sda3 904GB |
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> |
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> Disk SSD: /dev/sdb |
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> /dev/sdb1 26GB |
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> /dev/sdb2 90GB |
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> /dev/sdb3 4GB |
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> |
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> And use /dev/sdb3 as swap. (I will add more with another SSD in future) |
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> /dev/sda3 mounted in /home/user/data (to save data unused) |
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Why put the swap on the SSD? |
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> And a RAID 1 with: |
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> md0: sda1+sdb1 / |
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> md1: sda2+sdb2 /home |
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> |
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> (sda1 and sda2 will be made with the flag: write-mostly. This is useful |
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> for |
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> disks slower). |
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> In a future, I'm going to add more SSD's on this RAID. My idea is the |
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> fastest I/O. |
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> |
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> Now. My problem/question is: |
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> Following the gentoo's |
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> doc<http://www.gentoo.org/doc/es/gentoo-x86+raid+lvm2-quickinstall.xml>, |
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> it says I need to put the flag --metadata=0.9 on the RAID. My question is |
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> ¿This will make get off the performance?. |
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metadata=0.9 might be necessary for the BIOS of your computer to see the |
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/boot partition. If you use an initramfs, you can use any metadata you |
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like for the root-partition. |
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> I only found this |
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> document<https://raid.wiki.kernel.org/index.php/RAID_superblock_formats#The_version-0.90_Superblock_Format>. |
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> This says the difference, but nothing about performance and |
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> advantages/disadvantages. |
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> |
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> Another question is, ¿GRUB2 still unsupporting metadata 1.2? |
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See reply from Canek. |
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> In case that metadata get off performance, and GRUB2 doesn't support this. |
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> ¿Anyone knows how can I fix this to use metadata 1.2? |
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> |
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> I don't partitioned more, because I saw this unnecessary. I just need to |
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> separate /home in case I need to format the system. But if I need to |
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> separate /boot to make it work, I don't have problems doing that. |
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> |
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> But of course, /boot also as RAID... |
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/boot seperate as RAID-1 and metadata=0.9 and you are safe. |
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> ¿Somebody have any ideas to make it work? |
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It is similar to what I do, except I don't have SSDs in my desktop. |
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I have 2 partitions per disk: |
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1 : /boot (mirrored, raid-1) |
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2 : LVM (striped, raid-0) |
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All other partitions (root, /usr, /home, ....) are in the LVM. |
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I use striping for performance reasons for files I currently work with. |
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All important data is stored and backed up on a server. |
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For this, an initramfs is required with support for mdraid and lvm. |
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> Thank you all. Bytes! ;) |
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You're welcome and good luck. |
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Please let us know what the performance is like when using the setup you |
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are thinking off. |
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-- |
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Joost |
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