Le 22/12/2015 20:03, koukou73gr a écrit :
Even the cheapest stuff nowadays has some more or less decent wear
leveling algorithm built into their controller so this won't be a
problem. Wear leveling algorithms cycle the blocks internally so wear
evens out on the whole disk.

But it would wear out faster, as wear leveling targets using *all* pages the same number of times, even the ones which are already used. That's another cause of write amplification for you. [0]

[0] https://en.wikipedia.org/wiki/Write_amplification#Wear_leveling

Even more so, on cheaper SSDs, where the wear leveling algorithm may be somewhat less intelligent than on so-called "data center" SSDs.


-K.

On 12/22/2015 06:57 PM, Alan Johnson wrote:
I would also add that the journal activity is write intensive so a small part 
of the drive would get excessive writes if the journal and data are co-located 
on an SSD. This would also be the case where an SSD has multiple journals 
associated with many HDDs.


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