Hacker News Reader

> But simpy put; on modern disks the logical block address has no relation to the position of the head on the platter.

WD kind of tried that with device managed SMR devices and they show absolutely horrible re-silvering performance.

Without a relatively strong relations of linear write/read commands and their physical locations also being mostly linear, spinning rust performance is not on a usable level.

View on HN

DMSMR is an issue yes, but CMR disks already do it and it's not as much of an issue as you think. On a CMR this is entirely fine.

The issue with SMR is that because a write can have insane latencies, normal access gets problems.

CMR doesn't have those write latencies, so you won't face resilvering taking forever.

It also helps if you run a newer ZFS, which has sequential resilvers that do in fact run fine on an SMR disk.

I will also point out that wear leveling on a DMR disk tries to achieve maximum linear write/read performance by organizing commonly read sectors closer to eachother.

Reply on news.ycombinator.com