insulatior ware = electrons may migrate through lattice
Broken lattice bonds = lattice traps electrons
Write amplification happens when pages are moved from block column to empty space so that block column can be erased.
Data sequentially written minimizes write amplification
SSD disks do garbage collection
HHD: 75 Billion I/O in 5 years
SSD: 1.433 Billion I/O in 5 years
SATA SMART ID 202 repports life remaining
Total bytes read
SSD TBWL
3.5 pb
seconds in 5 years
means ~9K iops/second allowed
Steady state performance, write performance
Enterprise assunmes no idle time for write management
Personal drives assumes bursty activity
Lots of idle time for write management
Host tells host to inform ssd that data is no longer used
Rahter than wait for newer version of existing data
Not honored on enterprise drives
Vendor will quote power off retention time.
non-interuptable block erase command for all blocks on the drive