Large Crowds Are Not the Reason for Assassin's Creed: Unity's Framerate Issues

It isn't the volume of NPCs that are leading to Assassin's Creed Unity's performance issues, but an 'overloaded instruction queue', Ubisoft has said.
In an update on its official website, Ubisoft said that it had "received a lot of feedback on the performance of ACU over the past week and we're taking it very seriously. Ensuring that you get the best gaming experience is part of the reason we make games in the first place, so hearing that the game isn't performing as expected for some of you is cause for serious concern. We know this is a very important issue to you and we want to see it resolved as much as you do.
"We've been investigating this since launch," it continued, "because this type of issue requires a great deal of attention and care in both finding the root causes and resolving them. It's taken us some time to make progress on this front, but we've got some promising findings to share."
As a result of its investigation, Ubisoft says that it has "detected a distinct discrepancy between what we observed in the pre-launch versus post-launch environment. In spite of our testing, it looks like the instruction queue is becoming overloaded and impacting performance."
"We have several fixes we are exploring right now and will continue to update you with our progress of what is working and how quickly we can implement these fixes in the game in the weeks ahead."
The publisher says that it is also looking into the following revisions that should help "improve framerate stability":

• Streamlining some technical aspects of navigation: We've fixed a number of edge cases with our detection system to smooth certain behaviors during parkour. We've fixed a few objects which were improperly tagged to smooth navigation.
• Improving task scheduling: We've tuned the way the computing tasks are prioritized and parallelized by the processor cores to improve framerate in certain edge cases.
• Tweaking performance for Reach High Points: We've optimized the reach high points, during the camera swooping sequence to improve framerate a little bit.

"Though crowd size was something we looked at extensively pre-launch, it is something we continue to keep a close eye on," Ubisoft added. "We have just finished a new round of tests on crowd size but have found it is not linked to this problem and does not improve frame rate, so we will be leaving crowds as they are."