I had it on my list of things to possibly try, a tar in | tar out copy to see if it yielded different results.
On its face, it seems like cp -a is getting ever so slightly better speed, but not a clear night and day difference. I will definitely look into this and report back any findings, positive or negative. Thanks for the suggestion, Reed > On May 28, 2021, at 3:24 AM, Matthias Ferdinand <mf+ml.c...@mfedv.net> wrote: > > On Thu, May 27, 2021 at 02:54:00PM -0500, Reed Dier wrote: >> Hoping someone may be able to help point out where my bottleneck(s) may be. >> >> I have an 80TB kRBD image on an EC8:2 pool, with an XFS filesystem on top of >> that. >> This was not an ideal scenario, rather it was a rescue mission to dump a >> large, aging raid array before it was too late, so I'm working with the hand >> I was dealt. >> >> To further conflate the issues, the main directory structure consists of >> lots and lots of small file sizes, and deep directories. >> >> My goal is to try and rsync (or otherwise) data from the RBD to cephfs, but >> its just unbearably slow and will take ~150 days to transfer ~35TB, which is >> far from ideal. > > (Disclaimer: no experience with cephfs) > > I found rsync a wonderful tool for long distances and large files, less > so for local networks and small files, even with local disks. > > Usually I do something like > > ( cd src/ && tar --acls --xattrs --numeric-owner --sparse -cf - . ) | > pv -pterab | > (cd dst/ && tar --acls --xattrs --numeric-owner --sparse -xf -) > > If src and dst are not mounted on the same machine you can use > netcat/socat to stream the tar from one system to the other, or pipe it > through ssh if you need encrypted transport. > > This does not have the resume capability of rsync, but for small files > it is much faster. After that you can still throw in a final rsync for > changes accumulated while the initial transfer was running. > > Matthias _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-le...@ceph.io
