On Tue, 26 Jan 2021, Greg A. Woods wrote:
The lore I was told at the time was that you alwasy
ran three and that
it didn't matter if they were all on the same line with semicolons or
not because of the very fact that the second one would block.
What I was taught was:
% sync
% sync
% sync
and never:
% sync; sync; sync
The theory was that by waiting for the shell prompt each time, it gave the
buffer pool enough time to be flushed.
The third one was just for superstitious good luck,
and just in case
there was a process still running and writing to a filesystem.
Never heard that theory, but naturally you did a "ps ax" first, didn't
you?
-- Dave