In a recent update posted on Helldivers 2’s Steam page, developer Arrowhead’s deputy technical director, Brendan Armstrong has explained the cause behind the third person shooter’s humongous 150 GB size on PC which is around three times the game’s size on the consoles. And according to him, most of it is due to data duplication that’s used in Helldivers 2 and the nature of the mechanical hard drives along with their inner workings.
“The main issue with a mechanical HDD is seek time. An HDD stores data on a spinning platter, and a physical arm with a read head has to move across the platter to find and retrieve data. The time it takes for this arm to “seek” or move to the correct location is a significant performance bottleneck.”
“Imagine a large game level with various objects — trees, rocks, buildings, props. If the data for these objects is scattered all over the hard drive, the read head has to physically jump around the disk, which adds a lot of time to the loading process,” Armstrong stated.
He also provided Arrowhead’s solution to the problem of seek time in HDDs, which is Data Duplication:
“To solve this problem, we deliberately duplicate certain data files (like a common tree texture or a sound effect) and place copies of them in physically close proximity to where they would be needed in the game.
For example, our build system will ensure that a copy of a tree texture is stored on the same part of the disk as the level geometry data. When the game loads the level, the read head can access all the necessary information in a single, continuous sweep, without having to “seek” to a different location. This dramatically speeds up loading times.”
However, the dev also admits that in case of SSDs which use flash memory chips for storing data and have no moving parts like HDDs, the problem of seek time is practically nonexistent. But as HDDs are still largely used in the PC Gaming community, the devs have no other option but to include workarounds like Data Duplication for them.
He also added more insights on Helldivers 2‘s technical status while acknowledging some of the pressing concerns the game is having right now, but also confirming that they are looking to find balance “between loading times and installation size soon”.

