On Sat, 31 Aug 2024 02:52:20 +0200 Exuvo <[email protected]> wrote: > I have been trying to figure out why tar run by amanda was so much > slower than my manual tar runs. The culprit is tar --sparse (which is > on by default in amgtar) which for me maxes out 1 CPU core and > reduces tar's read speed to around 130MB/s for me on a ZFS filesystem > with 1GB files. I turned that option off and now it can read at > 500MB/s with only 30% CPU usage.
Thank you. I tried this on one of my machines. But first I checked to see whether there were sparse files out there, which might affect the size of the backups. Apparently a lot of files are created sparse. But that doesn't mean the data is sparse, or sparse enough to cause problems. Preliminary results are encouraging. I haven't examined the results closely, but plan to monitor it on that machine. -- Does anybody read signatures any more? https://charlescurley.com https://charlescurley.com/blog/
