1+9 is rather dilute for D-76 (which is a Kodak developer, by the way). The most that I have ever diluted it was 1+5, and that is fairly unusual. Going from memory I used times of around an hour or an hour and a half, with an EI of 1600 to 3200 for Tri-X.
Why do you want to dilute it so much? You would need to be careful about minimum developer volume.
I see that the Massive Development Chart doesn't give times for 1+9. I'd guess that Tri-X in D76 at 1+1 is the most common film/developer combination in use, and for very good reasons. Check this thread on APUG called "Wow! D-76 Is Actually Pretty Good". I know Helen is a member of APUG as well, and I know that if you asked the question over there you would get many more answers than you will here, but they would all tell you pretty much what Helen has already said.
D76 is Kodak's version of Ilford ID-11 - just looked at a box of that and the highest dilution it lists is 1+3 = 19 minutes for Tri-X, but you probably know that already.