FreeBSD and Linux SSD Write Speeds

[JD]

On 06/21/2017 12:33 PM, Tim Daneliuk wrote:
> On 06/21/2017 11:27 AM, Valeri Galtsev wrote:
>> sync; date; dd if=/dev/zero of=foo bs=8M count=512; sync; date
> So I just did this:
>
>     sync; date; dd if=/dev/zero of=foo bs=8M count=1024; sync; date
>
> And got this:
>
> Linux:
>
> Wed Jun 21 13:30:22 CDT 2017
> 1024+0 records in
> 1024+0 records out
> 8589934592 bytes (8.6 GB, 8.0 GiB) copied, 33.523 s, 256 MB/s
> Wed Jun 21 13:30:57 CDT 2017
>
>
> FreeBSD:
>
> Wed Jun 21 13:28:23 CDT 2017
> 1024+0 records in
> 1024+0 records out
> 8589934592 bytes transferred in 46.508336 secs (184696666 bytes/sec)
> Wed Jun 21 13:29:10 CDT 2017
>
> So ... still a pretty big disparity
>
> I don't want to test against a raw device or partition because that's
> not how these systems get used.  My FreeBSD FS is UFS and maybe that
> simply is not as efficient on an SSD as ext4.
>
> This isn't a big deal, just an eyebrow raiser for me.  I've used FreeBSD
> as a production OS since 2.x and have always found it to be consistently
> quicker and have a smaller footprint than Linux.  This was just a surprise.
By my prior use of BSD and after that FreeBSD, the UFS was never
a shining star of disk I/O speeds.