Most of the speedup is due to ssh being bound to a single CPU. You will get a little more speed out of a single CPU system but the speedup is unlikely to go past 2 in parallel. Even with that you may end up adding more latency via disk seeks to accomplish much.
On 8/24/21 5:12 PM, hancooper wrote: > ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ > On Tuesday, August 24, 2021 8:25 PM, Kevin Korb via rsync > <rsync@lists.samba.org> wrote: > >> In my experience backing up multiple hosts to a single host can speed >> things up. Especially if using rsync over ssh with multiple CPUs on the >> single host. You would need to do some experimentation to determine the >> best number for your hardware and network. Also, if you exceed that >> number you can put more stress on the backup machine lessening the >> impact to the hosts being backed up. >> >> On 8/24/21 3:58 PM, hancooper via rsync wrote: >> >>> It makes sense to we to run multiple rsync commands to speed up a backup. >>> At work, some have argued that if I sync the data all to the same host, >>> there is no advantage >>> in parallelization. Whether you sync 3x 1G in parallel or 1x 3G makes >>> no noticeable difference. >>> Speed in general does not increase by increasing the number of sync >>> processes. >>> However, if one want to sync to multiple hosts, the effort may be >>> worthwhile. >>> What is the current advice about speeding up data transfer ? >> >> -- >> Kevin Korb Phone: (407) 252-6853 > > > Hi Kevin. What about a single host to another with multiple CPU's ? > -- ~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._., Kevin Korb Phone: (407) 252-6853 Systems Administrator Internet: FutureQuest, Inc. ke...@futurequest.net (work) Orlando, Florida k...@sanitarium.net (personal) Web page: https://sanitarium.net/ PGP public key available on web site. ~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._., -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html