Saving plots to pdf, using latex for font rendering (i.e. setting rcParams['text.usetex']=True) results in very large file size (~150kb for simple line plot with some mathematical latex expressions). This is due to all fonts being fully embedded into pdf.

When resulting pdf is postprocessed, so that only subset of fonts is embedded, file size is reduced drastically (e.g. from 150kb to 15kb).

The embedded fonts are of FontType=1.

Pdf backend should support embedding of subset of fonts when rcParams["text.usetex"]=True is used.