ZFS Optimizing for large directories and MANY files

[mike tancsa]

On 6/25/2019 2:19 PM, mike tancsa wrote:
> /|# time find . -type f -mtime -2d|/
>
> /|takes 40 min after a cold boot.|/
>
> /|Watching zfs disk IO, its super slow in terms of bandwidth, but gstat
> shows the disks close to being pegged.  I guess the heads are thrashing
> about inefficiently ?


Just for comparison, I tried the same test on the new box that will be
in production. With SSDs (instead of spinning metal) the same find on a
cold boot takes

1.318u 55.396s 1:21.96 69.1%    35+176k 865535+0io 0pf+0w

and the second time through, just

1.102u 48.666s 0:49.96 99.5%    35+177k 169189+0io 0pf+0w


    ---Mike