Timeline for Do solid-state flight recorders use wear levelling?
Current License: CC BY-SA 4.0
9 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 18, 2020 at 3:47 | comment | added | Vikki | Explain thyself, cowardly downvoter. | |
| Feb 18, 2020 at 3:38 | comment | added | CrossRoads | I don't know what kind of memory is used in FDRs. One type that would be great is Ferroelectric RAM (FRAM), which can have 10 trillion write cycle capability and not need battery backup to retain the data. 10^14. One could write to 1 location once a second for 317 years before wearing it out. | |
| Feb 17, 2020 at 22:48 | comment | added | Jan Hudec | @h22, also, most embedded devices don't have special wear-levelling controllers, but use log-structured filesystems to avoid non-uniform wear. Wear-levelling is only used on memory cards and SSDs designed as drop-in replacement for spinning disks because the filesystems designed for spinning disks are particularly bad in this regard, FAT being the far worst. | |
| Feb 17, 2020 at 22:42 | comment | added | Jan Hudec | @h22, there is nothing stopping you from writing a flash memory linearly just like a tape. Then it does not have any mapping table. I don't know whether they actually do that, but it would make most sense. | |
| Feb 17, 2020 at 19:30 | review | Close votes | |||
| Feb 18, 2020 at 4:19 | |||||
| Feb 17, 2020 at 18:42 | answer | added | selectstriker2 | timeline score: 4 | |
| Feb 15, 2020 at 23:10 | comment | added | h22 | The question is, where that table of mappings is stored. One of the obvious places to store it is to use part of the same memory chip, storing nothing in the controller. | |
| Feb 15, 2020 at 20:45 | comment | added | Fiddlesticks | I would be surprised if flight recorders do employ wear-levelling. That technique is really only useful in a situation where some memory locations are undergoing significantly more write cycles than others. But flight recorders, by their very nature, record information cyclically. | |
| Feb 15, 2020 at 20:23 | history | asked | Vikki | CC BY-SA 4.0 |