Article : A look at STL/CLR performance for linear containers

~ Nish

This article is an attempt to do a performance comparison of the STL/CLR sequential containers with corresponding generic collections in the BCL. To my total surprise, the STL/CLR containers fell way behind the BCL classes. Talk about misleading expectations. 😦

Unknown's avatar

Published by Nish

5 thoughts on “Article : A look at STL/CLR performance for linear containers”

  1. Nice article Nish,
    I’m suprise too about this performances.

    I thought stl/clr was designed only for using native object in containers. My guess is that perfomance wasn’t the first purpose.

    Reply

  3. I just copied and ran your code. I used just a simple command line and just the insert and remove test.
    Using 10000000 iterations
    With Debug build, I got

    List:306
    Vector:1297

    Using Release
    List:254
    Vector:424

    It seems that the performance is still slower, but not nearly as bad once the optimizer gets a chance at it

    With Release

    Reply

  4. Here is some more data from running the iterator and sort tests

    For release I chose the favor fast code optimization and inline any suitable

    Debug

    InsertRemove (List vs Vector vs StdVector)
    244
    1188
    3648
    Iterate (List vs Vector vs StdVector)
    217
    1338
    2629
    Sort (List vs Vector vs StdVector)
    927
    2102
    10194
    Press any key to continue . . .

    And Release version
    InsertRemove (List vs Vector vs StdVector)
    288
    414
    387
    Iterate (List vs Vector vs StdVector)
    247
    463
    298
    Sort (List vs Vector vs StdVector)
    939
    717
    308
    Press any key to continue . . .

    Some early conclusions
    1) The STL code is absolutely dependent on the optimizer

    2)The std::stl with optimizer hangs in with the BCL for most tests and stomps it in the sort test.

    3) The cliext::stl is slower than the std version but manages to also win handily in sorting

    Nishant, do you know if you had optimizations enabled

    Reply

  5. Nish, This is a very good exposé. Were you in debug mode suffering from MDA problems? (See Jeff’s comments and link on your page at http://blog.voidnish.com/?p=94. I’ve seen no mention of that problem being fixed.) If not, I’m as surprised as you!! This is a very strong indictment against the compiler. It must be generating code that thunks and copies at every turn, none of which is necessary. If no fix for the compiler is on the horizon, many of us in industry will have to reevaluate how, where, and (in some cases) even if managed C++ can play a role in our competitive markets. Thanks much for this heads up.

    Reply

Leave a Reply