Difference between pages "Help talk:Funtoo Editing Guidelines" and "Solid State Drives (SSD)"

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{{DISQUS}}
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{{PageNeedsUpdates}}
 
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This page aims to highlight SSD relevant options for commands commonly used during system setup/install.<br />
Please keep DISQUS at top and use DISQUS for new discussions. It renders quickly for me.
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'''<big>SSD</big>'''<br />
 
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'''WARNING'''<br />
__TOC__
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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 />
 
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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 />
== console output ==
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LUKS<br /> cryptsetup luksFormat --align-payload 2048 (default)<br />
there are no examples of console output.
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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 />
<pre>
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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 />
<console>###i## some command
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vgcreate -s 4M (default)<br />
output
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MKFS<br />mkfs.ext4 -b 4096 -E stride=128,stripe_width=128 (erase block size / 4096) (for raid1)<br />
output
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mkfs.xfs -b 4096 -d sunit=1024,swidth=1024 OR -d su=512K,sw=512K (for raid1)
</console>
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</pre>
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produces
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<console>###i## some command
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output
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output
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</console>
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== Seo friendly spaces ==
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it should be noted that google indexes seo_unfriendly_url as seounfriendlyurl while it indexes seo-friendly-url as seo and friendly and url keywords. thus we should prefer - instead of _ for spaces.
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http://www.funtoo.org/Web-server-stack <--- good
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http://www.funtoo.org/Funtoo_Linux_Installation <--- bad
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see http://youtu.be/_CbNXj3YlK4
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== Fancy Boxes ==
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TODO: Describe fancy* boxes, and explain the most fool-proof way of using them. Use this format, exactly:
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{{fancyimportant|1=
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Now you can put lots of funky stuff in here, like <tt>html</tt> tags, etc, and not
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have a problem with the parameter getting passed as the first parameter.
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Cool!
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}}
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== ebuild documentation ==
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http://www.funtoo.org/Adding_an_Ebuild_to_the_Wiki
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i think the first part should have a link to adding the build wiki info.  the pages should be linked against each other.  & or transclusion at the bottom of this help article. (and a very minor note that the file stuff should be bundled into the fancy notes at the bottom.)  =D  <3 u guys
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== Special Characters ==
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To produce pipes: <pre>{{!}}</pre>
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generates: {{!}}
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(i think equals needs a similar template?)
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{{fancynote|That's right {{=}} I added it}}
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Note that in general cases you can use the <code><nowiki><nowiki></nowiki></code> markup that displays inner content as-is, but for a single character that might have lots of occurrences that's quite a pain.
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== delete template ==
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to flag a page as a candidate for deletion, insert
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<pre>{{delete}}</pre>
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at the top of a page.
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{{delete}}
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[[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) 16:54, 20 September 2014 (UTC)
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== Minor edits ? ==
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Should we use the checkbox "This is a minor edit" and when should we use it ? I often forget to set this option when I make what I consider a "minor edit", but what is the purpose? Is it somehow useful? -- [[User:Pytony|Pytony]] ([[User talk:Pytony|talk]])
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: http://www.funtoo.org/index.php?title=Special:RecentChanges&hideminor=1 <--- you can hide minor changes...  like duncans recent flooding of the logs with category changes on templates should all be minor changes, if not double tisk ;-) [[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) 22:41, 26 September 2014 (UTC)
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::Oh that's right, thanks. Maybe this could be good to add in the page, dear BDFL :P -- [[User:Pytony|Pytony]] ([[User talk:Pytony|talk]])
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:::I really think we need a section explaining NOT to edit for W to w or category changes ONLY....  this is really a shortcoming in mediawiki not detecting "stub edits" and moving them out of the primary logs.  this morning looking at the changes i see all these tiny commits, with out content being rolled in also.  in all reality minor edits is poorly designed in the base web app and should be bug reported upstream.  it should be include minor edits, rather than exclude minor edits.....  [[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) 01:28, 4 October 2014 (UTC)
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== video playlists ==
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i have several examples of how to embed playlists in [[Programming]] but there are no examples in how to wiki.  im moving some of these issues to upstreams bug tracker....  the - links & stub edits are really problems upstream should be dealing with.
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== how to talk pages ==
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we need a section explaining how to indent for step2 of talk threads
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:ie conversation 2
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:: ie convo 3
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::: we need info on using tilde's to sign and date etc... noting that its good practice to sign with 4 ~
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{{tip| <pre>~~~ && ~~~~ && ~~~~~</pre> produces [[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) && [[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) 22:41, 26 September 2014 (UTC) && 22:41, 26 September 2014 (UTC)}}
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we need a note about user talk pages being a messaging system....  (i put a disqus on my talk page so i get email notifications when people say things to me) [[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) 22:41, 26 September 2014 (UTC)
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== template requests ==
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=== external resources ===
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I would like a sexy little widget for by the top of the page with links to: tldp, wikipedia, ohloh, cvedetails, github, sourceforge, etc with sexy little icons.  It will make our pages feel more interwoven with the larger linux community. ;-) [[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) 23:30, 2 October 2014 (UTC)
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http://www.cvedetails.com/vendor/12010/Mariadb.html
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=== fortune of the day ===
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I'd like a daily fortune rotation on my user page to show im looney tunes ;-) [[User:Threesixes|Threesixes]] ([[User talk:Threesixes|talk]]) 23:30, 2 October 2014 (UTC)
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== chat ==
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Revision as of 13:11, December 1, 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. <ref>https://wiki.archlinux.org/index.php/SSD_Memory_Cell_Clearing</ref>
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)