Crontab time format question

for Linux crontab time format 

*/22 * * * *

shouldn"t it be executed every 22 minutes?

but look at the output 

14:44:00
15:00:00
15:22:00

Why is it that at 44 minutes, it should be 66 after 22 minutes, that is, 6 minutes after the next hour? why is there zero?

Centos
Mar.04,2021

from Wikipedia

https://en.wikipedia.org/wiki/Cron

Please note that frequencies generally cannot be expressed; only the number of steps evenly divided into their ranges indicates the exact frequency (minutes and seconds, that is, 2 go) 3 / 4 / 5 / 6 / 10 / 12 / 12 / 15 / 20 and / 30, because 60 is divisible by these numbers; a few hours, i.e. / 2 / 2 / 3 / 4 / 6 / 6 / 8 and / 12); All other possible "steps" and all other areas produce inconsistent "short" periods at the end of the "reset" to the next minute, the next day or before the next day; for example, depending on months and leap years, the date field of entering * / 5 is sometimes executed 2 or 3 days later; This is because cron is stateless (it doesn't remember the last time it was executed, nor does it calculate the difference between it and now, which is needed for accurate frequency counting-on the contrary, cron is just a pattern matcher).

Google translation, there may be inarticulate.

first of all, / not the usage in the POSIX standard
then, the step frequency can only be set to the value of "divisible time span".
for example, for minutes and seconds, the step frequency can be 2, br, 3, 4, 5, 6, 10, 12, 12, 15, 12, 20, 30,
for hours, the step frequency can be 2, 3, 4, 4, 6, 8, 12, 12,

cron is just for pattern matching. It is stateless and does not record when you start executing.
so if it is not divisible, it will have an unexpected effect

.
for minutes and seconds, that's / 2, / 3, / 4, / 5, / 6, / 10, / 12, / 15, / 20 and / 30
because 60 is evenly divisible by those numbers;
for hours, that's / 2, / 3, / 4, / 6, / 8 and / 12

Cron

quoted from wiki

this is performed every 22 minutes, not every 22 minutes, with 22 minutes * give it a try

Previous: Vue cross-domain problem, cookies can not carry, CAPTCHA?

Next: How to implement vue routing nesting routing, similar to this one

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b4015a-2c4e0.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b4015a-2c4e0.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?