Why?

DBUS is approximately 18 times slower than CORBA

From CORBA, DCOP and DBUS. A performance comparison

So why has everyone dropped Corba?

Hereìs the whole paper, written many years ago.

There is also another oldish document at https://wiki.gnome.org/Accessibility/Documentation/GNOME2/ATSPI2-Investigation/IPCResults (last edited in the 2013) showing similar results.

As far as I can sey CORBA is now regarded as legacy. But the need for good performances will never become legacy. So people still ask for “modern CORBA replacement“. There are several answers: Web Services, ICE and TAOX11. And I surely miss the best one.

Other people directly ask “is CORBA outdated?”

The short: Yes, sadly, CORBA is outdated, as in:

• No decent .NET implementation
• The existing C++ binding is ugly, although there does exist a new C++11 binding
• No decent implementations for other modern languages (except Python)

That being said, existing CORBA implementations like omniORB, TAO, R2CORBA are supported and used, and are IMHO much more mature than many other IPC/RPC frameworks, although these are certainly more “modern” and are probably the future.