:: Re: [DNG] noatime by default
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Autore: Narcis Garcia
Data:  
To: dng
Oggetto: Re: [DNG] noatime by default
El 28/08/17 a les 11:59, Alessandro Selli ha escrit:
> On Sun, 27 Aug 2017 at 17:18:28 -0500
> d_pridge <d_pridge@???> wrote:
>
>> Doesn't this affect the expected lifetime for an SSD?
>
> Little. AFAIK this used to be a more serious concern on the first
> generation of SSDs, because they suffered strongly from write-wear and
> because firmware, drivers and filesystems did not support write-levelling.
> Today this is much less of a concern. SSD cells can stand many more write
> operations before wearing (not so so called 3D SSD units, however) and unit's
> firmware today apply algorithms to write operations that attempt to spread
> writes as evenly as possible to cells avoiding impinging too many times on
> the same ones. Which means that, even if you're writing several times on the
> same filesystem's blocks (e.g., the FS's log on a journalled FS), these
> blocks are mapped to cells spread here and there on the SSD that are generally
> different from write operation to another, transparently to the filesystem's
> driver and block allocator. Plus, SSD-aware filesystems (designed, among
> other things, to reduce the impact of write amplification of cells being
> rewritten) further help prolonging the unit's life, regardless of how it is
> used.
>


"SSD-aware filesystems" are flesystems mounted with no atime