> From: smurfd <[email protected]> > Date: Sat, 20 Jun 2026 18:55:25 +0200 > > Then on NetBSD, installed on the SSD i did this: > > # gpt destroy wd0 **** > # gpt create -Af wd0 **** > # gpt add -t raid -l raid5@wd0 -b $(( 2048 )) -s 15628051053 wd0 ****
What was the alignment of this partition? Does it make a difference if you use `-a 4096' or `-a 1m' with `gpt add'? zfs will warn if you try to `zpool add' a disk that natively uses 4096-byte sectors but advertises 512-byte sectors, implemented under the hood by a read/modify/write cycle, if the starting sector is not aligned to avoid the r/m/w cycles. The message will look something like: ZFS WARNING: vdev ...: sectors are misaligned (alignment=..., firstaligned=...) (In a future zfs update, if I recall correctly, `zpool add' will be able to handle this misalignment on its own instead of telling you to realign the partition.) However, I don't think raidframe detects and warns about this case. And perhaps gpt(8) should also use the disk's native alignment as the default alignment instead of 512 bytes. You should watch `iostat -x wd0 1' while you're doing writes to see if the underlying disk's throughput and latency look reasonable.
