Hello Jennifer,
Thanks for your quick answer,
I would like to upload large fasta files and make it available to the user interface for analysis with galaxy tools.

I will have a look at the uploading/data librairies wiki page here : https://bitbucket.org/galaxy/galaxy-central/wiki/DataLibraries/UploadingFiles.
 
I 'll give you a feedback.
Thanks,
greetings,
Ben