As Seagate expands shipments of its new Heat Assisted Magnetic Recording (HAMR). Mosaic 3+ hard drive platform, the company is in the enviable position of shipping the first major new hard drive technology in a decade, and the less enviable position of proving the reliability of the first major new hard drive technology in a decade. Due to HAMR's use of intermittent heating with its platters, as well as all new read/write heads, HAMR introduced a number of new changes at the same time that begs the question of how reliable the technology will be. . Looking to address these issues (and further develop their HAMR drives), Seagate has published a recent blog post. An outline of the company's R&D efforts, and why the company expects their HAMR drives to last many years – as long or longer than current PMR hard drives.

Mosaic 3+ drives have the same reliability as conventional drives that rely on Persistent Magnetic Recording (PMR), the company says. In fact, the components of HAMR HDDs have shown a 50% increase in reliability over the past two years. Seagate says the Mosaic 3+ drives boast impressive durability metrics: their read/write heads have demonstrated the ability to handle more than 3.2 petabytes of data transfer over 6,000 hours, typical of 20 times faster than the data transfer of nearby hard drives. Accordingly, Seagate is rating these drives for a mean time between failure (MTBF) of 2.5 million hours, in line with PMR-based drives.

Based on their field stress tests of more than 500,000 Mosaic 3+ drives, Seagate says the heads of Mosaic 3+ drives will last seven years, surpassing the typical lifespan of current PMR-based drives. In general, users estimate that modern PMR drives will last four to five years with average use, so these drives will exceed current expectations.

Overall, Seagate continues to aim for a seamless transition from PMR to HAMR drives in customer systems. This means ensuring that these new drives can fit into existing data center infrastructure without requiring any changes to enterprise specifications, warranty terms, or form factors.