Nexus-6-AH-3

Nexus 6 Encryption Latency Likely Due to Missing Qualcomm Drivers

November 25, 2014 - Written By Nick Sutrich

Ever since the Nexus 6 launched there’s plenty of buzz around the phone. Some people are wondering when they can finally get their hands on the device, while others are relishing the opportunity they had to order it from Google Play Store or their carrier of choice. On the software side, however, we’ve seen some concerning news about disk write speeds on the Nexus 6 when compared with basically every other high-end phone out there. At first, some were wondering what the deal was, then we learned that it was Google’s new built-in encryption on the phone that was slowing things down, constantly needing to encrypt and decrypt information on the disk. Worst yet, there’s no way to turn this off on the Nexus 6 outside of a factory reset and installing a ROM that has encryption disabled, which leaves the majority of users out in the cold when it comes to having options to speed up their device.

But there’s something interesting at play here that wasn’t previously considered. The Nexus 6, along with many modern Android devices for that matter, ship with something on-board their CPU called the Qualcomm Hardware Cryptographic Engine. This is supposed to be a hardware solution for encryption that takes the load off the CPU and frees up the disk, in order to let it to perform at its usual speeds by passing the data through this hardware layer for both encryption and decryption.  What’s odd, is that Google isn’t using this hardware layer of the Nexus 6 at all, which on the surface seems like a glaring oversight.  Breaking it down though there’s a couple explanations that seem plausible, but probably the most legitimate one is that these drivers for the QHCE are probably not open source, and as Android goes that’s pretty much a no-no.

At this point there’s no telling whether or not Google plans to implement these drivers to enable the use of the QHCE, or at least significantly improve its performance is the layer is being used but we can hope they’ll work out a plan with Qualcomm to get these devices back up to par with others out there.  That being said, even with these relatively low speeds the Nexus 6 is just as fast if not faster than pretty much every other phone out there, and it’s likely a combination of hardware prowess elsewhere and the software finesse of Android 5.0 Lollipop.