I've noticed particularly for files stored on SMB, the time required for both save and autosave operations is almost entirely proportional to the number of old files in the data directory. Cleaning out the old files makes a dramatic improvement when there are just a few hundred. There must be a better way to optimize this.
When using v3.8 it seems like network latency is the largest factor in file save time. GnuCash doesn't work well offsite. But removing the backup files doesn't seem to make much difference anymore.
