I want it to last as long as I keep this computer . . .which given laptop 
lifetimes and the need to upgrade every 3 years or so means about 2 more years 
probably. Given that . . .it's a question of whether noatime will prevent SSD 
write life from being used up. When you average the number of writes over the 
whole 240 GB on the drive . . .then you end up with really long times to 
failure. OTOH, if you're constantly rewriting the same blocks due to modifying 
the directory entries for access time, etc . . .then conceivably it's a much 
shorter time since the writes aren't averaged over the whole drive but just a 
small subset of blocks.

In my research .  .I've seen statements that drive writes are randomized and 
that the directory blocks are constantly moved around on the SSD by the wear 
leveling routines in the drive firmware . . .but then there were the counter 
claims that only data blocks were randomized through wear leveling and not the 
directory blocks. I was unable to find any definitive statement on it.

My gut feeling is that you're right and the life shortening by not using 
noatime is minimal . . .but was looking for some sort of definitive statement.

On Mar 11, 2011, at 11:43 AM, Daniel Hazelbaker wrote:

> I would say it depends on how long you want your drive to last.  We just 
> purchased 2 128GB Samsung SSD drives for use with moving large files from one 
> city to another on a weekly basis.  After deep research through Samsung's 
> specs and expected time before writing begins to fail (they actually have 
> this documented) we decided we have plenty of time.  I forget exactly how 
> much data Samsung said you could write to it before it started having issues, 
> but we calculated how long it would last for us (which reversing the 
> calculation gives about 13TB of expected write life-time):


-----------------------------------------------
There are only three kinds of stress; your basic nuclear stress, cooking 
stress, and A$$hole stress. The key to their relationship is Jello.

neil



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