Can I enable discards on a LUKS-encrypted ssd drive in RHEL6 (and do I need to)?

Posted by Dan Nestor on Super User See other posts from Super User or by Dan Nestor
Published on 2013-10-27T20:11:33Z Indexed on 2013/10/27 21:56 UTC
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Filed under:

linux

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Performance

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ssd

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rhel

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trim

I have a RHEL 6.4 workstation, running on a LUKS-encrypted LV residing on a SSD. I found RedHat documentation stating that dm_crypt does not currently support TRIM passthrough, however I also found other sources that state the opposite (albeit for other distributions) and even that discards are not needed for recent SSD drives which use some sort of automatic garbage collection. So:

1) Can I enable TRIM/discards with my setup?

2) Do I need to, for optimal disk performance?

Thanks for your thoughts.

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