wastin

time's a-wasting

You are wasting or running out of time! "Wasting" is often shortened to "wastin'." Come on, get those chores done so we can get out of here. Time's a-wastin'! Time's a-wasting, kids! You're going to fail the assignment if your experiments aren't finished by the end of the class.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

time's a-wastin'

Rur. Time is running out.; It is getting late. Hurry up! Time's a-wastin'! How come you're still in bed? Time's a-wastin'!
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
See also:
References in classic literature ?
There no need 'a your wastin' your breath in long-winded arguments about this an' that an' th' other.
"We got enough to do to move nearer that water tonight, without wastin' time talkin'.
"All I got to say is you ain't wastin' any time gettin' together.
What's the sense o' wastin' canvas?" the farmer-sailor replied.
You can quit wastin money at motels and hostel whatevers.
How about council quits wastin money on ugly wastes of space and builds more places 4 them 2 go, if it wants them out the way so badly.
Second, according to the Exercitatio of 1641 German kings seeking to reassert control over a "Roman empire" narrowly defined as rule over the city of Rome were wasting their time; according to the De Germanorum imperio Romano they were not wastin g any time at all.