Compressing via blosc library

[eschnett]

I wonder how much work it would be to add blosc compression to ADIOS2, and how that would be best implemented? Would this best be handled by plugin? Are there examples for plugins? Does such a plugin exist already?

[anagainaru]

Blosc2 is already an operator within ADIOS2 that you can attach to your data. This is an example of using Blosc2:

        // add operations
        adios2::Operator Blosc2Op =
            adios.DefineOperator("Blosc2Compressor", adios2::ops::LosslessBlosc);

        variable.AddOperation(Blosc2Op, {{adios2::ops::blosc::key::clevel, accuracy},
                                        {adios2::ops::blosc::key::threshold, threshold},
                                        {adios2::ops::blosc::key::doshuffle, doshuffle}});

If you are interested in the internal implementation, the operator is defined here:source/adios2/operator/compress/CompressBlosc.cpp