JLD2 writes zeros to first 3440 bytes in file

[tiagopereira]

When writing arrays or other structures to a JLD2 file, it writes zeros to the first 3440 bytes in the file. Here is a sample code:

using JLD2
tmp = ones(Float64, 100, 100, 100)
jldsave("test.jld2"; tmp)
aa = load("test.jld2")["tmp"]

Then the read array aa will be zeros until element 431 (first 3440 bytes). If I instead write a Float32 array, then it is zero until element 861 (still first 3440 bytes).

This error persists if I write different structures with arrays. The array parts of the structure have also the first elements filled with zeros. There is no difference whether using the FileIO interface or jldsave.

Using Julia 1.10.0, JLD2 0.4.43 on Linux. The error only happens in Linux. Tested with a M1 Mac with Julia ARMv8 for and it worked fine.