As noted in
MGNLACTIVATION-43, currently the temporary file with activated content is written once per subscriber. So if e.g. a folder with files amounting to 500MB is activated on 4 subscribers, there are effectively 2GB written to disk in the process of activation.
If possible, the temporary file should be written only once per activation in order to reduce disk IO.
The actual writing of the file happens in info.magnolia.module.activation.Transporter.prepareTempFile(ActivationContent).