For 25-man raiders, input lag is the hottest news right now, and Lead Encounter Designer Ion "Watcher" Hazzikostas has put out a plea for information.
A while back, in late August, a thread was started
in the official forums talking about some experimentation players had done, trying to work out what was causing this occasional massive and problematic lag in 25-man raids. Since then, there have been some serious changes
made to various AoE heals, resulting in massive nerfs to spells like Healing Rain. And yet, according to the forums, and to our recent interview
with top guild Method, nothing has changed. The lag is still there, it's still a problem, it's still having a massive impact on players.
One forum thread has posted a fix for some weird nameplate/UI issues, which the poster also said might have an impact on FPS issues, but as Lead Encounter Designer Ion Hazzikostas clarifies in his post, lag is a term that can mean many different things for many different people. So if you're experiencing this lag, characterized by an absence of low framerates or high pings, start gathering information.
This is an issue that I personally care about tremendously, and it's no exaggeration to say it's discussed nearly daily in some capacity, among members of the design team and with our gameplay and server engineers. We made a number of changes to spells in patch 5.4, tweaking periodic and area-of-effect heals like Healing Rain to massively reduce the number of discrete healing events yielded by each spellcast while keeping overall throughput largely similar. Since 5.4 has released, we've continued to make performance improvements to effects like Soul Link (batching up multiple damage events into a single heal to you and your pet rather than triggering a dozen tiny heals when you AoE a group of creatures), and our investigation continues. We know that it doesn't matter how well-designed or fun a boss encounter is in the abstract if you have to struggle with basic control elements while facing it.
Continued feedback and data from players who experience the specific type of input delays described in the excellent original post of this thread would be helpful and appreciated. But while I am no technical expert, it is important to note that "lag" can be a potentially misleading catch-all term that is used to describe a variety of different types of problems. The hallmark of the input delay issue described at the outset of this thread is that it occurs despite having consistently high FPS and low ping to the server. Some of the more recent reports of sharp FPS dips almost certainly have other causes. For example, for players reporting massive framerate drops when entering Norushen's trials, the most likely cause lies with a UI mod that needs to be updated or replaced (likely a unitframe mod in particular). Other cases of poor framerate in the outdoor areas of the raid are more likely a video card or graphics settings issue. Those are valid concerns for feedback and discussion, but would better be directed to the Technical Support forums for discussion there.
If you'd like to discuss the specific type of performance issue outlined at the start of this thread
, including updated examples of Siege of Orgrimmar fights where the problem is most apparent, or whether there has been noticeable improvement since 5.4, that would be very welcome.