[Nottingham] SSD upgrade

[Martin]

On 11/02/14 12:59, Jason Irwin wrote:
> On 11/02/14 12:55, Martin wrote:
>> Rather than waste time with Marketing games and ignorance, just assume
>> 16MiB or if you're really keen, pull off the covers and look up the
>> flash chip numbers... :-)
> Just got it and don't want to break it on the second day!

You shouldn't be able to do it any harm by just merely writing to it.

Keep it away from pets and any children ;-)


And for the alignment... Don't worry too much about that. The really
important alignment is to ensure 4kB alignment for the 'sectors'.
Another sweet-spot is to use an aligned filesystem that works in 8kB or
16kB chunks (btrfs has just moved to 16kB for improved performance).

And, when aligning, you are fine to align to any multiple of whatever
the aligning unit is. So assuming 16MiB for your partitions is a good
idea and can't hurt regardless of whether that alignment can actually be
for your device 256kB or 512kB for professional expensive devices or
2MiB or 4MiB for present "consumer grade" stuff.


Enjoy the aligned speedup!

Have fun,
Martin


ps: No, SSDs do not physically have any HDD-style sectors, but that
style of operation is assumed throughout the software stack still!

ps2: The next development may well be moving to 'RAM + FLASH' modules
whereby the CPU accesses both system RAM /and/ flash storage all as one
continuous address space... That could eliminate the SATA bottleneck.


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