It would be nice if the Linux (and Android) client used the O_NOATIME flag when opening files just to check them. The documentation (from "man 2 open") reads thusly: O_NOATIME (Since Linux 2.6.8) Do not update the file last access time (st_atime in the inode) when the file is read(2). This flag is intended for use by indexing or backup programs, where its use can significantly reduce the amount of disk activity. This flag may not be effec‐ tive on all file systems. One example is NFS, where the server maintains the access time. I think btsync is very similar to the intended use case for this flag!