Why is Bloomberg API working slower when adding "blpapi3.jar" as a dynamic library instead of static library?

I am using the Datafeed Toolbox and I am executing "blp/history" function and requesting a lot of data.

When I use "blp/history" with a dynamic path, it may take hours to complete running. However, with a static path, it is much faster and it can be done in about 20 minutes or so.

Why does "blp/history" perform so much slower when I use the dynamic path rather than the static path?

Answer 1

[MathWorks Support Team]

The function "blp/history" has two possible code paths depending on how "blpapi3.jar" is added to the classpath.

If "blpapi3.jar" is added:

- statically, then MATLAB is able to use code in "datafeed.jar" that parses the event messages at the Java level and then passes a Java vector back to MATLAB. There is only one MATLAB/Java boundary crossing in this case and it is much faster.

- dynamically, then MATLAB is not able to resolve what it needs at a startup making the code in "datafeed.jar", that relies on "blpapi3.jar", inaccessible. In this case, "blp/history" falls back to using the MATLAB code path, which makes the Java calls directly from the MATLAB Workspace and there are many MATLAB/Java boundary crossings needed to parse the event messages. Thus, this implementation is much slower.

Add "blpapi.jar" to the static Java path rather than the dynamic path. That is, define a "javaclasspath.txt" rather than using "javaaddpath" - this will give you the best performance. See the section "Add Jar File Classes" in the MATLAB documentation page about the static Java classpath:

https://www.mathworks.com/help/matlab/matlab_external/static-path-of-java-class-path.html#bvjg_eg-3

Additionally, if Bloomberg API is still slow after adding it to the static path, try downloading the 'blpapi3.jar' from Bloomberg again and replace it in your current installation.

[Rena Berman]

(Answers Dev) @Matt Marek the rest of the Answer has been restored.