On 09/04/2022 09:00, Yolo von BNANA wrote:
Can you please explain this in more Detail?
What does this mean: " "systemctl reload" will basically return
immediately without the reload being complete"?
And what is an Example for an synchronous command for ExecReload=
Do you understand the difference between "synchronous" and
"asynchronous"? The words basically mean "aligned in time" and "without
timed alignment".
Think of writing to files. In the old days of MS-DOS et al, when your
program called "write", the CPU went off, saved the data to disk, and
returned to your program. That's "synchronous", all nicely ordered in
time, and your program knew the data was safe.
Now, when your linux program calls write, linux itself replies "got it",
and your program goes off knowing that something else is going to take
care of actually saving the data to disk - that's "asynchronous". Except
that sometimes the program needs to know that the data HAS been safely
squirreled away (hence all these fsync calls).
So when systemd calls ExecReload *A*synchronously, it goes off and fires
off a load more stuff, knowing that the ExecReload IS GOING (future
tense) to happen. What the previous poster wanted was a synchronous
ExecReload, so that when systemd goes off do the next thing, the
ExecReload HAS ALREADY HAPPENED (past tense). (Which in general is a bad
thing because it *seriously* knackers performance).
Cheers,
Wol
