How many tunes do you maintain in your repertoire? I mean those ones you’d be confident to perform in public for pay.
DJones
In Low Whistle about 35 tunes…with Ups none, zip, nada… 
If you’re talking about busking, you’ll only need about ten tunes. Played three times each, by the time you come round to number one again, the listeners wil have passed on. If you mean a payed gig on stage, then enough tunes to get you through about 45 minutes without repeating.
I did a wedding the other week where I played for an hour and a half non-stop and surprised myself by not having to repeat any tunes. All the oldies just kept coming back to me.
DavidG
Something 135 min ( 3x about 45min sets) continiously playing UP with my band.
And some moore tunes just alone.
Then GHB’s and borderpipes (+bodhran) quite many pieces…
“I play the bodhran, I know EVERY tune!” 
Ontopic: Not many, maybe 20 tunes. But it also sometimes happens that I hear a tune and can play it but can’t remember having practised it anytime…mysterious.
I read somewhere that the truly accomplished and experienced Irish musician will have somewhere in the neighborhood of 500 tunes in his/her repertoire. Some great musicians may have a bit fewer than that, while others (the button box player Paddy O’Brien [of Chulrua] comes to mind)may know hundreds more. Of course, likely only a fraction of these tunes may be simultaneously at the tip of a musician’s brain and fingers to be played at a moment’s notice. Irish musicians tend to live in fear of the supposedly “common” tunes they don’t know that they think everybody else does.
I generally tend to try and have about 30-35 sets of tunes (with 2-4 tunes per set; I’m too lazy to go through and count them all now) in performance-quality order at all times just in case the all-too-rare gig should come along. Somewhere around 25-30 sets should be more than enough for about a 3-hour gig.
… without a doubt, he certainly does.
I, unfortunately, have a very small repertoir of tunes that I can play on the pipes. This is due to having spent more time in the last five years fiddling with reeds than actually playing. I guess I can confidently play about 20 tunes, which is pretty pittiful if you ask me.
I’ve played the piano for 21 years and can play heaps of tunes, plus being an accomplished ‘play by ear’ pianist, any tune that I can hear in my head can be transported throught the keys so the number would be well into the 100’s.
I’ve ordered a new chanter that I am hoping won’t cause me grief with reeds so I can work on actually becoming a good uilleann pipe player and increase my repertoir.
Goldy.