Cardiff scored twice, but could have had a few more if they had taken their chances against Arsenal.
The Gunners were eventually able to seal their victory late through Alexandre Lacazette.
The Bluebird's performance gave Warnock some encouragement, as they looked potent against Emery's side, despite the final score.
"We had quite a lot of chances, with a lot of bodies in the box, and they've listened. We could have had six or seven and against Arsenal, that's the pleasing thing for me," Warnock said.
"It was tough, but I really enjoyed the game. We were always in it, we missed some great chances, and your top teams take a few of those."
However, despite the good sides of the performance, Warnock was still aware that his side need to improve:
"A couple of the goals were disappointing. Lacazette was unbelievable but the centre-half shouldn't have had a free header from the corner. It wasn't their fantastic play that leaves someone at a corner, or turns and shoots in the near post, that's defending that we need to be better at."