Hours of tiny transfers at the end of a ZFS resilver?

[Ravi Pokala]

>Date: Tue, 16 Feb 2016 09:09:17 +0000
>From: Steven Hartland <killing at multiplay.co.uk>
>To: freebsd-fs at freebsd.org
>Subject: Re: Hours of tiny transfers at the end of a ZFS resilver?
>Message-ID: <56C2E73D.2010405 at multiplay.co.uk>
>Content-Type: text/plain; charset=windows-1252; format=flowed
>
>This is 4k underlying, SSD's are by far and away the worst culprits for this.

On the one hand, you're right - SSDs actually *do* lie about their 512n/AF-512e/AF-4Kn designation. On the other hand, SSD erase blocks - and even program blocks - are larger than 4KB, so neither AF-* designation would be correct anyway. And to some extent, it doesn't matter for SSDs, since everything is so heavily indirected anyway.

-Ravi (rpokala@)