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Comment by sullrich | Hacker News Reader

I am also seeing really poor write speeds when comparing to my Linux droplets. 11MB/sec vs. 216MB/sec on Linux

With FreeBSD, in order to be able to have automatic backups work, we were required to disable journaling on the disk. This will cause the disk speed to be much slower than our Linux distributions.

If you wish to have higher disk speeds, but not use backups, we recommend for you to remount your disk with journaling. https://www.freebsd.org/doc/en/articles/gjournal-desktop/con...

Why did journaling interfere with automatic backups?

journaling generally interferes with dump(8). It seems odd that they would be using dump to do backups though, since they are virtualizing the OS.

The parent link to gjournal is weird too, since gjournal is not the same as softupdates w/journaling (SU+J). It makes me wonder if they actually disabled softupdates too.

I found a random post[1] about issues (unmapped io?) running i386 freebsd with su+j in virtualbox (apparently a virtualbox bug[2]).

[1]: https://forums.freebsd.org/threads/freebsd-10-i386-data-corr...

[2]: https://lists.freebsd.org/pipermail/freebsd-current/2013-Nov...

DO disabling journaling is a big deal.

What else has DO disabled and/or modified from a vanilla install?

DO modifies a lot of stuff on vanillas installs. They're one of the only providers I know of that removes the swap partition.

Where does DO document all of the modifications they make to a vanilla FreeBSD install?

That deserves an explanation - you can backup non-ext2 linux partitions, surely? What have I misunderstood?

This should be done by default on droplets which do not have backups enabled.

> required to disable journaling on the disk

Shouldn't this make it much faster as the FS no longer maintains a journal?

So I enabled Journaling and that brought it up to 30MB/sec. Still a substantial difference vs 216MB/sec for Linux.. Something with the D.O. KVM HOST setup needs to be tweaked a bit - 30MB/sec is pretty poor quality disk throughput for SSD attached storage.

There is no way to boot into single user mode for now (or at least instructions provided aren't working).

And the reason was invalid /boot/loader.conf:

console="vidconsole,comconsole" autoboot_delay="10" console="comconsole,vidconsole" autoboot_delay="1"

Second console actually disables access from web console access, which is fatal.

Autoboot is not critical, although default to 3 sec should work much better for opportunity to change boot options from web console.

This got apparently fixed, in my "ams3" instance I've had to issues getting web console to work (needed to "tunefs -n enable /")

I just use Vultr and install from a FreeBSD downloaded ISO. No modifications to the base install at all and works as expected.

DO have screwed something up with their configuration if they need to make so many changes to make it work. No other VPS provider I have used that support FreeBSD (or OpenBSD for that matter) require any changes to the default install.

On UFS soft-updates have a lower overhead than soft-updates with metadata journaling. The downside of soft-updates without journaling is that it requires a background fsck to recover leaked space after unclean shutdowns. I prefer UFS2 SU (not SU+J) on FreeBSD for small systems, because SU+J is incompatible with UFS snapshots.

Are these the same datacenter? The same rack? I suspect that degraded instances and overly-busy disks are not endemic to AWS.

Mine are both in NYC3, so same datacenter. No clue regarding rack/host. I can't comment on AWS...

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