I'm trying to copy a directory from an EXT4 filesystem to a NFS mount, but write performance so slow, it is around 100 KB/sec.
Source directory have about 5000 small files (from 5Kb to 300Kb) and length of the filenames around 64 bytes.
When I try to copy a single large file on the same setup, I'm getting 25 MB/sec write performance which is quite acceptable for me. But, with the directory described above, it is nearly impossible to complete copy operation.
I tried with nfs cache (fsc), noatime, nodiratime, rsize and wsize options without any success.
Filesystem on the NFS server is XFS, so working with 5000 files in a directory is not a hard job for the NFS server.
What can be wrong with this setup? How can I increase the file copy performance?