Difference between pages "FLOP:Funtoo New Ebuilds" and "Ssd"

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(Created page with "This page aims to highlight SSD relevant options for commands commonly used during system setup/install.<br /> '''<big>SSD</big>'''<br /> '''WARNING'''<br /> Avoid using dd co...")
 
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{{FLOP
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This page aims to highlight SSD relevant options for commands commonly used during system setup/install.<br />
|Created on=2014/01/03
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'''<big>SSD</big>'''<br />
|Summary=This is a proposal for a Web page similar to en.znurt.org.
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'''WARNING'''<br />
|Author=Aramis qc,
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Avoid using dd command to overwrite data on SSD. The SSD controller has its own algorithms for allocating writes based on its internal topology. Trying to overwrite data the usual way (e.g. dd if=/dev/zero of=/dev/sda ) is not only futile but will reduce the remaining number of writes to the flash cells. To inform the controller that all data can be purged use hdparm --security-erase. <ref>https://wiki.archlinux.org/index.php/SSD_Memory_Cell_Clearing</ref><br />
|Maintainer=Aramis qc
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Partitioning<br />The default alignment of 1MiB provides for proper SSD performance. For gdisk, ensure each partition starts at integer multiple of 2048 (sectors). If you change gdisk's default boundary then the default for other programs may change as a result.<br />
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LUKS<br /> cryptsetup luksFormat --align-payload 2048 (default)<br />
This is a proposal for a Web page similar to [http://en.znurt.org/ znurt].
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cryptsetup luksOpen --allow-discards<br />
 
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MDADM<br />mdadm -c 512  Aligns chunksize to 512KB erase block size times 1 data disk (for raid1)<br />
==Weakness==
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LVM<br />pvcreate --data-alignment 512 (equal to value given as chunksize) ?default? --data-alignment-offset (should not be needed for correctly aligned partitions)<br />
 
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vgcreate -s 4M (default)<br />
Current znurt site does not support Funtoo ebuilds such boot-update and the likes.
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MKFS<br />mkfs.ext4 -b 4096 -E stride=128,stripe_width=128 (erase block size / 4096) (for raid1)<br />
 
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mkfs.xfs -b 4096 -d sunit=1024,swidth=1024 OR -d su=512K,sw=512K (for raid1)
==Advantage==
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The Funtoo New Ebuilds page takes into account Funtoo own ebuilds plus packages masked by Funtoo.
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That will permit anyone wanting to know about latest versions and packages available to access an informal page.
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[[Category:FLOP]]
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{{FLOPFooter}}
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Latest revision as of 10:04, 10 January 2014

This page aims to highlight SSD relevant options for commands commonly used during system setup/install.
SSD
WARNING
Avoid using dd command to overwrite data on SSD. The SSD controller has its own algorithms for allocating writes based on its internal topology. Trying to overwrite data the usual way (e.g. dd if=/dev/zero of=/dev/sda ) is not only futile but will reduce the remaining number of writes to the flash cells. To inform the controller that all data can be purged use hdparm --security-erase. [1]
Partitioning
The default alignment of 1MiB provides for proper SSD performance. For gdisk, ensure each partition starts at integer multiple of 2048 (sectors). If you change gdisk's default boundary then the default for other programs may change as a result.
LUKS
cryptsetup luksFormat --align-payload 2048 (default)
cryptsetup luksOpen --allow-discards
MDADM
mdadm -c 512 Aligns chunksize to 512KB erase block size times 1 data disk (for raid1)
LVM
pvcreate --data-alignment 512 (equal to value given as chunksize) ?default? --data-alignment-offset (should not be needed for correctly aligned partitions)
vgcreate -s 4M (default)
MKFS
mkfs.ext4 -b 4096 -E stride=128,stripe_width=128 (erase block size / 4096) (for raid1)
mkfs.xfs -b 4096 -d sunit=1024,swidth=1024 OR -d su=512K,sw=512K (for raid1)
Cite error: <ref> tags exist, but no <references/> tag was found