11–20 of 58 posts
Fascinating analysis. I know planes get used a lot, but I'm surprised that they go for such a long time without ever being powered down.
51 days seems to be approximately how often my mac dies in kernel panic or starting to be bugged by persistent software problems that go away with a restart.
Fascinating analysis. I know planes get used a lot, but I'm surprised that they go for such a long time without ever being powered down.
51 days seems to be approximately how often my mac dies in kernel panic or starting to be bugged by persistent software problems that go away with a restart.
Was it a cost issue?
Or was there an expectation that a regular maintenance check would occur within this time frame that involved a reboot as part of the maintenance check for diagnostics?
Earlier quoted context omitted.
51 days seems to be approximately how often my mac dies in kernel panic or starting to be bugged by persistent software problems that go away with a restart.
I’m at 356 days of uptime on my MacBook Pro. ¯\_(ツ)_/¯
For example, let’s imagine that the timestamp set by the transmitting ES is close to its wrap-around value. After performing the required calculation, the receiving ES obtains a timestamp that has already wrapped-around, so it would look like the message had been received before it was actually sent. Isn't it surprising that modulo arithmetic, as already employed successfully in TCP sequence numbers and the like, sti…
To address the second part: > and yet the plane appears to have no mechanical backup instruments[?] This is unlikely in a modern aircraft because mechanical instruments to back up e.g., the artificial horizon / attitude indicator or directional gyro (DG) / heading indicator are: 1) Mechanically complex - the attitude indicator and DG make use of gyroscopes which rotate at up to 24,000 RPM along with other mechanisms.…
It's sort of like how you don't need RAID for your offsite backup disks, just some parity for bit-rot.
The mechanical instruments would be the (additional) redundancy. The additional weight/lines/service is indeed burdensome even without redundant mechanical systems.
For example, let’s imagine that the timestamp set by the transmitting ES is close to its wrap-around value. After performing the required calculation, the receiving ES obtains a timestamp that has already wrapped-around, so it would look like the message had been received before it was actually sent. Isn't it surprising that modulo arithmetic, as already employed successfully in TCP sequence numbers and the like, sti…
To address the second part: > and yet the plane appears to have no mechanical backup instruments[?] This is unlikely in a modern aircraft because mechanical instruments to back up e.g., the artificial horizon / attitude indicator or directional gyro (DG) / heading indicator are: 1) Mechanically complex - the attitude indicator and DG make use of gyroscopes which rotate at up to 24,000 RPM along with other mechanisms.…
It's just not a workable idea in general. There are checklists for stuff like instrument failure which can probably recover from a software bug like this.
Earlier quoted context omitted.
51 days seems to be approximately how often my mac dies in kernel panic or starting to be bugged by persistent software problems that go away with a restart.
I’m at 356 days of uptime on my MacBook Pro. ¯\_(ツ)_/¯
Earlier quoted context omitted.
51 days seems to be approximately how often my mac dies in kernel panic or starting to be bugged by persistent software problems that go away with a restart.
I’m at 356 days of uptime on my MacBook Pro. ¯\_(ツ)_/¯