Just asked AI and it seems to depend on what hardare controller you have and it varies between consumer , enterprise drives , Unless it's just making stuff up?
A consumer NVMe drive capable of 500,000+ random write IOPS can plummet to just 200 to 400 IOPS under a heavy fsync load (like a transaction database or Proxmox virtual disk). Its latency spikes into milliseconds, making it perform closely to an old spinning hard drive.
Why Enterprise M.2 Drives Escape the BottleneckEnterprise M.2 NVMe drives (such as the Samsung PM9A3) feature built-in hardware capacitors for Power Loss Protection (PLP).
When an enterprise drive receives an fsync, it can safely instantly acknowledge (ACK) the write the millisecond it hits the drive’s internal onboard DRAM.The drive knows that if power fails unexpectedly, the onboard capacitors hold enough physical charge to safely flush that RAM data into the flash chips anyway.
Because of this, enterprise NVMe drives can easily process 40,000+ fsync operations per second instead of a few hundred.