Why should I use Nexenta anyway?

As we've already learned, Nexenta is based on Ubuntu, with an OpenSolaris kernel (not unlike Debian GNU/kFreeBSD or Debian GNU/Hurd). So why should I use Nexenta, since Ubuntu is probably supported/used by more people, and supports more hardware?

You should use it because it has outstanding mainline features. You won't have to patch your kernel or otherwise use unsupported features to get instant access to ZFS, DTrace, Containers, Fault Management, 32/64-bits multiarch, ...

Also, Solaris is known to be one of the best OSes out there when it comes to multi-threading, which is great with today's CPUs with multiple cores and hardware threading (such as Intel HyperThreading or Sparc CMT).

Outstanding Features

Let's dig into more details about what Nexenta can bring you:

• ZFS: easy dynamic storage management (no SoftRAID + LVM + fs + mountpoints) of use disk capacities, reliable (COW, RAIDZ), fast, with snapshots (which also bring you system clones with rollback, usable as fail-safe upgrade paths, because of integration with your bootloader (GRUB or OpenFirmware)), deduplication and compression, Flash log devices (for best performances)
• DTrace: dynamic tracing of your software (want to diagnose anything happening on your machine now or in a timely manner?)
• Containers: Linux Vserver made easy. Simply put: a way to isolate processes
• Fault Management: SMF (completely replaces init scripts and inetd, and offers more features) and more
• 32/64-bit: Solaris has been natively 32/64-bit for years, as is the Sparc architecture, historically its primary target platform

Solaris' excellent multi-threading probably explains why it is recommended in the following applications:

• Recommended OS for Asterisk, the Open Source Telephony Project
• Performs exceptionally well with high-performances Java multi-threaded applications