# ZFS - HAST - TRIM - SSD - Do they work well together?



## GeorgeLinn (Oct 5, 2013)

Was curious if using SSDâ€™s with HAST and ZFS affect how ZFS supports TRIM on SSDâ€™s ?  Would HAST inhibit ZFS ability to manage\support TRIM in any way?   

Thanks.
George


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## FreeDomBSD (Oct 6, 2013)

I believe that ZFS can be made SSD-aware through configuration.

with some googling action I have found you a news release for 9.2:
http://www.phoronix.com/scan.php/?page=news_item&px=MTQ3MzU

and a posibly useful reading:

http://constantin.glez.de/blog/2011/02/frequently-asked-questions-about-flash-memory-ssds-and-zfs

I hope this helps!


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## GeorgeLinn (Oct 9, 2013)

Thanks for those details!  Regarding the link from http://www.phoronix.com explaining â€œ*FreeBSD's ZFS file-system implementation now supports TRIM for solid-state drives (SSDs)â€*.  If you use HAST with ZFS and are feeding your ZFS pools HAST devices that are SSD based, does ZFS still offer TRIM support?  Does ZFS even realize that it is dealing with SSDâ€™s anymore since it is actually accessing a HAST device?  Hope I am making sense


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## mav@ (Oct 14, 2013)

ZFS doesn't need to know that it runs on SSD. It is all about BIO_DELETE method support by the device. Unless device return error on attempt to use it, ZFS will use it. I have never used HAST, but as I can see in its sources and man page it does know about it.


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## GeorgeLinn (Oct 15, 2013)

Thanks Mav@!


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