Apple’s new ARM-based M1 Macs reportedly suffer from a mysterious issue that results in excessive SSD wear. The allegation stems from various users across social media and hardware forums (e.g., LTT and MacRumors), who have posted drive monitoring data confirming abnormally high levels of drive writes within a relatively short period of time. One user even suggests that the SSD in the 256 GB model could reach its TBW (terabytes written) limit in as little as two years.
“One user showed that their M1 Mac had already consumed one percent of its SSD after just two months, while another M1 Mac with a 2TB SSD had already consumed three percent,” MacRumors wrote in reference to tweets from Longhorn and David that showed 150 TB and 15.7 TB of writes, respectively. “The total data units written for these machines is running into many terabytes, when they would normally be expected to be considerably lower.”
16GB M1 MBP, 2TB SSD, 2 months in. pic.twitter.com/SaSmieaT1s— David (@david_rysk) February 15, 2021
“The user with three percent usage speculated that, were his machine a 256 GB model, it could have used as much as 30 percent to date, and have reached maximum TBW in around two years. An SSD can continue to function once its TBW limit has been reached, but there is no knowing how long it will last past this point.”
It isn’t clear whether the excessive SSD wear is due to a hardware problem related to the M1 chip or a software bug in the latest version of macOS, but some Apple users have found this issue pretty alarming because the SSDs are soldered and can’t easily be replaced. There are also reports of this problem cropping up on older, Intel-based Macs, which suggests that the issue might be more widespread.
Update on M1 SSD wear issue: Available data suggests that write endurance ratings are not proportional to drive size.— Hector Martin (@marcan42) February 16, 2021
256GB model: ~2000TB [1700-2300]
2TB model: ~5000TB [4300-6000]
This means that @david_rysk's currently known worst case would push a 256GB model to 100% in ~2y