Diablo IV Might Become the Second PC Game to Support Microsoft’s DirectStorage API to Lower Load Times

According to dataminers (via Reddit), the Diablo IV beta included files apparently related to Microsoft’s DirectStorage, the API created to lower load times in games by taking advantage of SSD hardware.

As you can see in the image below, there are two files named dstorage.dll and dstoragecore.dll. It should be noted that Blizzard Entertainment did not make any announcement regarding DirectStorage yet, so the developers may still be working on fully implementing the feature for the final version of the game.

If that turned out to be correct, Diablo IV would become the second PC game to officially support Microsoft’s DirectStorage, following Luminous Productions’s Forspoken.

DirectStorage was first released as a developer preview in July 2021, with the 1.0 launch of the API happening in March 2022. That was right around the time of last year’s Game Developers Conference, where Microsoft tried to push the API as not only useful to reduce load times but also to free up CPU cycles that could be used elsewhere in the game.

Software Engineer Cooper Partin said at the time:

Now, reducing the CPU overhead. This is a key benefit that I really want to stress. The more CPU cycles that are freed up for a title, they can be leveraged elsewhere in that title, improved background processing. AI workloads or anything, additional experiences, for example.

DirectStorage handles smaller reads really efficiently, and you can batch things together to get more work done. When fully integrated with your title, DirectStorage with an NVMe SSD on Windows 11 reduces the CPU overhead in a game by 20 to 40 percent. This is attributed to the advancements made in the file IO stack on Windows 11 and the improvements on that platform in general.

Unfortunately, that’s not what we saw in Forspoken, where a recent patch improved performance but increased load times. Forspoken is based on DirectStorage 1.0, which doesn’t include the GPU decompression introduced with version 1.1; however, the Diablo IV file inspected from the beta also seems to be based on version 1.0.2 rather than the most recent one.

Speaking of Diablo IV, the beta concluded a few hours ago. You can check out my impressions here; as a reminder, the game will release on June 6th on PC, PlayStation 4, PlayStation 5, Xbox One, and Xbox Series S|X. Pre-order customers will enjoy four days of early access.

Diablo IV will support NVIDIA DLSS 3 at launch. Blizzard also confirmed that ray tracing would be added to the game with a post-launch update.