On 6/9/20 9:44 AM, rhkra...@gmail.com wrote:
In the case of rdiff-back, it wouldn't surprise me that diffs (deltas) are stored as forward deltas, and, in removing old deltas, a new "base" must be created before deleting the deltas. (My words probably aren't exactly correct, I hope they are correct enough to explain my point.)
That's not how rdiff-backup works. The diffs are _reverse_ diffs, working back from the current state. Any metadata or increments file with a date stamp older than the cutoff date can be simply deleted. I suspect that the problem is the time spent parsing all of the file names in the _huge_ increments directory tree and comparing the date code. Speaking the the huge increments tree, a pet peeve of mine is that changes that do not affect file content cause a "zero diff" file to be generated. These can be changes to permissions and ownership, or even just a change to the hard link count. The files are typically compressed empty files, and are not empty themselves (there is at least a gzip header). I run an audit to get rid of most of these at the end of each day, after all clients have completed their backups. The first time I ran it, the count was well into the millions. -- Bob Nichols "NOSPAM" is really part of my email address. Do NOT delete it.