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Cc: freebsd-hackers@freebsd.org
Subject: Re: proper newfs options for SSD disk
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> You may be able to find the exact erase block size in the technical
> documentation of your specific SSD.  But the manufacturers don't always
> tell. :)
>
>
>> b) small fragments (like 1KB) to reduce space usage, as there is no
>> seeking so it will not slow down but save space on relatively small SSD
>
> I don't think you would want to write lots of very small fragments to
> any SSD. :)

i do - i have quite a lot of small files. with 4kB fragments i am losing 
10% of space.

but found it is right settings - Sandforce controller actually manages 
data with 4kB blocks.

>
>
>> c) anything else?
>
> Be sure to use "-t enable" when creating the filesystem:
>
>     -t enable | disable
>             Turn on/off the TRIM enable flag.  If enabled, and if the under-
>             lying device supports the BIO_DELETE command, the file system
>             will send a delete request to the underlying device for each
>             freed block.  The trim enable flag is typically set when the
>             underlying device uses flash-memory as the device can use the
>             delete command to pre-zero or at least avoid copying blocks that
>             have been deleted.

already done. thanks