Running X++ as IL has some huge performance benefits, but you have to be careful. Here is a write up of the changes we went through for the code compare tool in AX 2012 to increase its performance and reduce some IL side effects.
In Dynamics AX 2012 the compare tool has been through two significant changes to improve performance.
The first change was a re-implementation of the algorithm. In AX 2009 (and previous) the algorithm was “home-grown” – in AX 2012 it was changed to use the Longest Common Subsequence algorithm. For texts that were nearly identical this yielded little improvements – but for vastly different texts it became significant. To measure the performance improvement a “typical” text was defined as a text where 10% of all lines contained random text. The new algorithm (orange) could compare two typical texts each with 1100 lines in 10 seconds – the original algorithm (red) could “only” handle 650 lines in 10 seconds.
As the algorithm is pure CPU extensive– there is no database involvement- it could benefit significantly by running the code as IL. Switching over to run X++ code as IL is quiet simple in X++. By running the code as IL we can compare 4300 lines in 10 seconds. (green). To change the compare code to run as IL, here is what we had to do:
XppILExecutePermission perm =
By changing to a better algorithm and running the compare algorithm as IL, we have increased the size of texts that can be compared in 10 seconds from 650 lines to 3400 lines – a factor of 5. For small texts the difference is insignificant – the larger the text, the larger the gain. However; if the user disables IL ,then gain from running IL is gone, and a penalty is paid for the IL specific optimizations implemented. In this case it was an optimization to reduce memory consumption.