Several questions about the seafile Community Edition

Community Edition, centos7 environment, deploy MySQL database, use memcached+Nginx.
1, the "end of file, that is to upload the file to the VaR directory, and then cache to seafile problems, how to avoid this phenomenon does, directly to upload data to the seafile, rather than through the past (VaR var cache partition space is limited, such as multiple users simultaneously upload files over var space will cause data can not upload problem), or whether the problem because of the use of memcached is a normal phenomenon?
2, on the web side to delete files, cleaning disk space operation, look at the forum, someone proposed the following method
Upload large files, delete large files, empty the database recycle bin.
./, stop,./, stop,./
./, start,./, start.
Upload small files to the same database, delete small files, empty the recycle bin of the database.
./, stop,./, stop,./
Question: if the file is uploaded by multiple users, it also requires each user to delete the file, and then empty the recycle bin. Finally, will the administrator go to the server to empty the work?
3. Can the community version seafile-data directory be moved to an external storage server after installation?