3 ms·
Yeah, from a SRE perspective, the last N writes are always purely probabilistic. The real quest is to have enough redundancy that that curve is fairly close to
by GauntletWizard 11y ago
Yeah, from a SRE perspective, the last N writes are always purely probabilistic. The real quest is to have enough redundancy that that curve is fairly close to 1, and enough failure warning that your system will fix itself before it droops. That means Battery Backup, SMART detection, ECC memory, etc.
- planckscnst 11y agoIt's even worse than that. All writes have some probability of being incorrect, even after having been written to disk properly (the programmer did the right thing, the OS did the right thing, the filesystem did the right thing, and the disk did the right thing). After writing, your data can be modified by actions on other cells or by simply leaving it alone completely (see read disturbance and charge leakage). Some of this can be fixed by error correcting codes, but there is still a chance of loosing data simply by doing nothing wrong. So yes, agreed++. You need to have a level of redundancy appropriate to the criticality of the data.