[GTALUG] New Desktop PC -- debian Linux - Proposed 2 TB HDD Partitioning;

[Russell]

On April 18, 2018 8:35:41 AM CDT, lsorense at csclub.uwaterloo.ca wrote:
>> I guess that would mean that scattering unused space on an SSD
>between the partions, means the controller probably sees it as being
>used. I left chunks allocated at the ends of the drives as recommended.
>I was just wondering if my stripes would increase that wear level
>capability, as well as providing for emergency recovery space(s).  
>
>Trying to guess how a drive does its wear leveling is impossible.
>Even if you are buying SSDs directly from the manufacturer and have a
>relationship with them, they usually won't tell you how it works.
>
>Usually the drive has some extra space by design that it can use as a
>pool for writes, and then the old blocks are erased and put into the
>pool.
>If you use trim, you can add currently unused space in the filesystem
>to
>that free pool too.  Some drives will occationally move data that never
>changes from blocks that have very few writes to blocks that are more
>work
>in the hopes that it will then be able to use those better blocks for
>more
>frequently changing data, but simpler drives may not do such
>housekeeping.
>There really isn't any way to know, unless they choose to advertise it.
>Of course it is likely a drive with a much higher promised number of
>write cycles likely is doing smarter housekeeping to keep block wear as
>even as possible.
>
>I am not currently convinced that keeping unallocated space is worth
>it.
>Sure you make the free pool a bit larger, but you still end up writing
>the same amount of blocks and you make the usable size smaller.  Having
>a
>larger free pool might help for systems that do a lot of writes since
>you are more likely to be able to have a free block to do a write,
>while the drive hasn't had time to erase the old blocks.  On the other
>hand if you are doing enough writing that it could be a proble, maybe
>and SSD is the wrong type of drive to be using.
>
>I have all my SSDs fully allocated and see no reason to do otherwise.
>Some people have some crazy theories that often have no facts behind
>them.
>They just assume the drive makers are dumb and haven't thought of this
>amazing problem that they just thought of.  Of course some of the
>really
>cheap drives really are that dumb.

Thats what I tell people about my Phone. Its a smart phone. It just has a dumb operator. :-)

I've always left bits of HDDs unalocated for emergency recovery installs. Live distros on usb make that provision unnecesary. Hugh also posted an interesting link to a page, I think it was on  blkdiscard for thinly provisioned SSD's. Haven't gone there yet, but soon will. 

Thanks for your followup.
>
>-- 
>Len Sorensen

-- 
Russell