I've collected a new phrase from my watching of British television, getting on, as in "How's he getting on?" From various contexts, I think I've gotten the meaning down to "how's he doing?" Anyway, I was wondering, is this phrase commonly used throughout the UK, or is specifically London argot? Second, does its use invoke any class stereotypes? I.e., would using it in formal situation reek of informality, is it very slang-y?
Google Ngrams shows "How are you getting on ?" as a common phrase from the mid 19th century most of which seem to be British publications.
From the usage I see, I would not classify it as slang. Rather just a colloquial way of asking "How do you do ?"
The Family treasury of Sunday reading, ed. by A. Cameron 1859
Household words, Volume 11 By Charles Dickens
I can find one American example from The Baltimore literary and religious magazine, Volume 1 By Robert Jefferson Breckinridge, Andrew Boyd Cross dated 1835
The Cambrige dictionary lists the common AmE variant of "getting on" as "getting along"
Based on the usage in a sentence, it lists the various definitions. I think usage D,E,F are quite typical in UK.
An example of usage:
Someone has a task they are taking care of and you would like to know how they are progressing with the task, you could ask them 'How are you getting on?' if it were obvious what task you were referring to.
If it were not so obvious what you were referring to, you may refer specifically to the task, such as 'How are you getting on with that book you're writing?'
I'm from Newfoundland Canada and the phrase "How are ya getting on?" is still in daily use here. It means "how are you doing" or "how is life treating you".