I have observed this behavior consistently now across 5 or 6 official servers located both in the EU and US. When pressing Tab to open my inventory, the whole screen freezes for about a second before the inventory opens. This happens most often when the server is highly populated, and / or my character is located in a busier area.

My PC setup exceeds the recommended settings for DayZ, so it is not a hardware issue on my end.

This issue does not always happen when the server is lower population. It is annoying however and undesirably affects gameplay, as having to wait a few seconds to use my own inventory means that opening the inventory can be costly during a fight. Attached is a video of the stuttering behavior that makes it pretty clear to see. This behavior has been observed by several other players I've spoken to as well.

1. Play on any Official server when the player count is high (30-40+)

2. Press Tab (or whatever key) to open Inventory

3. Observe as the game freezes for a second or so

Inventory should open smoothly and without delay, as it sometimes does when the server is at a lower population level