The “load” and “save” functions run very slowly?

The “load” and “save” functions run very slowly?

When I load a mat file with a size of nearly 2G, it is very slow. It takes about ten seconds to get into memory. Save is also slow. Can Mathworks provide performance for these 2 functions?

my envs:

os: windows10

memery:16G

card: nvidia 1070-8G

matlab:r2020a

cpu: i7-6700 ,8-cores

[Ameer Hamza]

See matfile(): https://www.mathworks.com/help/releases/R2020a/matlab/ref/matlab.io.matfile.html. At least this will allow not to load the entire file if you want to access a few variables.

[xingxingcui]

Thank you for your prompt reply! But when the matfile() function loads my mat variable, it is still relatively slow, and a 2G file also takes tens of seconds. After actually imported into the workspace, it takes up 7.2G. Only one variable is saved in my mat file, As shown below：

[Dmitry Kaplan]

Consider yourself lucky. Saving a 2.2G table with -v7.3 takes 21 minutes, basically rendering the save() command useless. There are workarounds, but they are truly ugly.

Why is Matlab so lame with this? Good question. Serialization of tables, especially to files doesn't seem to be Matlab's programmers' strong suite (just try displaying a long table -- it can take a minute for Matlab to collect its thoughts before any output appears). Additionally, 7.3-style files are more complex and writing them takes longer in general. It is a pity that parallel toolbox's presence doesn't seem to help. I hope it will get better eventually.

If your datatype supports it, fwrite()/fread() are much faster.

[xingxingcui]

similar questions here, matfile and half inefficient storage