1 / 8

CORBA IN THE BALANCE Middleware & the Human Spirit AL GORE

CORBA IN THE BALANCE Middleware & the Human Spirit AL GORE. The CORBA C++ Mapping: Beyond Repair? MARS 2007 -03-14 Douglas C. Schmidt Vanderbilt University Institute for Software Integrated Systems. Disclaimer.

mira-dillon
Download Presentation

CORBA IN THE BALANCE Middleware & the Human Spirit AL GORE

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CORBA IN THE BALANCE Middleware & the Human Spirit AL GORE The CORBA C++ Mapping: Beyond Repair?MARS 2007-03-14Douglas C. SchmidtVanderbilt UniversityInstitute for Software Integrated Systems

  2. Disclaimer This talk presents my quixotic perspective as a long-time CORBA advocate & does not (necessarily) represent any company’s perspective

  3. Motivation

  4. What are the Problems? • Memory management is too complicated & easy to get wrong due to lots of rules to memorize, e.g., • Storing strings within sequences & structs • Not handling the return reference from an operation, but passing it to another operation • Not setting length() of sequence properly • Not duplicating object references properly • Not using ServantBase_var properly • Many of these problems stem from the lack of “self-managing” types in the C++ mapping

  5. What are the Problems? • Lack of standard C++ classes makes CORBA look “old & lame” & causes extra work for programmers • e.g., it’s a lot of work to move the data back & forth between the standard C++ types you want to manipulate & the types you need to pass as parameters • A tremendous amount of code gets generated for the C++ mapping, leading to bloat & slow compilation • The size difference between the same essential set of functionality can be roughly on the order of 5:1 • e.g., for e*ORB C & C++ on Red Hat 9 Linux compiled with gcc 3.2 the C libec_poa.so is 29 kbytes C++ vs libe_mpoa.so is 105 kbytes

  6. Top 10 Things to Fix in C++ Mapping • Fix valuetypes so they use consistent reference counting scheme • All types should offer exception-safe swap() operations • Use bool, wchar_t, wstring, std::string, std::vector, etc. • Do not introduce new types unless you must • Repeat number (1) until you reach (10) • All memory should be self-managed • This includes CORBA::Object, sequences, strings, structures of all types, etc • Structs & unions should have useful constructors • Arrays should be implemented using std::vector<> • Many more suggestions in CUJ columns by Vinoski & Schmidt • http://www.ddj.com/dept/cpp/184403757 • http://www.ddj.com/dept/cpp/184403765 • http://www.ddj.com/dept/cpp/184403778

  7. Why All This Is Hard • Tyranny of the installed base • Not clear what the strategic directions are for CORBA

  8. Ultimately, this isn’t a technical issue, per se, it’s a question of… Some Options • Wait for CORBA vendors to devise general fixes • Pros: Establish critical mass of vendors necessary to assure impact • Cons: To paraphrase the eminent Jay-Z: “I've got ninety nine problems but the C++ mapping ain't one” • Define an alternative mapping for a specific domain, e.g., embedded systems • Pros: Probably more realistic than trying to standardize a totally new general mapping • Cons: Doesn’t address the problem of trying to grow the overall general CORBA market • Define an alternative general mapping & prototype it via open-source ORBs • Pros: Let the market decide, i.e., similar to Boost for C++ • Cons: Establishing critical mass • Adopt the ICE C++ mapping wholesale • Pros: Well thought out & based on “modern” C++ • Cons: Legal implications, i.e., is the ICE spec “open”?

More Related