Microsoft has announced this it’s bringing its DirectStorage API to Windows PCs. The DirectX API was originally designed alongside the Xbox Series X Velocity Architecture, to hugely speed up loading times in games.
As we discussed in our developer deep-dive into SSDs and games, PCs have long used SSD storage but haven’t been able to take full advantage of the speeds provided for games for various reasons. This announcement should eventually bring SSD-equipped PCs, especially those with the latest NVMe technology, up to a par with the new generation of consoles.
The key here is the number of IO requests that modern games are making. In the past, games would stop and load large chunks of data (levels basically) into memory. Now of course, data is constantly streamed into games in a far more memory-efficient manner but that means there are many, many more times the number of IO requests.
“Unfortunately, current storage APIs were not optimized for this high number of IO requests, preventing them from scaling up to these higher NVMe bandwidths creating bottlenecks that limit what games can do. Even with super-fast PC hardware and an NVMe drive, games using the existing APIs will be unable to fully saturate the IO pipeline leaving precious bandwidth on the table,” said Microsoft’s Andrew Yeung in a blog post.
DirectStorage will solve that issue, handling the tens of thousands of IO requests a second that a modern game might make to fully utilise the bandwidth of NVMe, which has stepped up from merely hundreds in the past
“The overhead of each request is not very large and wasn’t a choke point for older games running on slower hard drives, but multiplied tens of thousands of times per second, IO overhead can quickly become too expensive preventing games from being able to take advantage of the increased NVMe drive bandwidths.”
NVMe will be “the storage technology of choice for DirectStorage and high-performance next generation gaming IO.” This is due to their NVMe queues, which “are particularly suited to gaming workloads.” And DirectStorage will make full use of these.
“We’re targeting getting a development preview of DirectStorage into the hands of game developers next year.”