pair<utime_t,utime_t> life_expectancy; ///< when device failure is expected
utime_t life_expectancy_stamp; ///< when life expectency was recorded
+ float wear_level = -1; ///< SSD wear level (negative if unknown)
void set_metadata(map<string,string>&& m);
void set_life_expectancy(utime_t from, utime_t to, utime_t now);
void rm_life_expectancy();
+ void set_wear_level(float wear);
+
string get_life_expectancy_str(utime_t now) const;
/// true of we can be safely forgotten/removed from memory