Re: [rdiff-backup-users] slow incrementals over ssh to localhost
On Thu, 8 Mar 2007, Jeff Strunk wrote: > Any ideas on increasing localhost performance? Is that the way it should be? use sudo with NOPASSWD. search for localhost: http://arctic.org/~dean/rdiff-backup/unattended.html -dean ___ rdiff-backup-users mailing list at rdiff-backup-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/rdiff-backup-users Wiki URL: http://rdiff-backup.solutionsfirst.com.au/index.php/RdiffBackupWiki
Re: [rdiff-backup-users] slow incrementals over ssh to localhost
On Thursday 08 March 2007 10:38 am, Randall Nortman wrote: > On Thu, Mar 08, 2007 at 09:59:20AM -0600, Jeff Strunk wrote: > > I just found that it takes 3 times longer to perform an incremental > > backup via ssh of the local machine than to perform the incremental > > backup directly. > > [...] > > It is most likely due to the CPU overhead of encrypting and decrypting > (and possibly compressing/uncompressing) byte of data that needs to be > "transferred". In fact, ssh to localhost can be slower than ssh to > another on the local network, because the CPU load is split between > the two machines. Given that rdiff-backup is a bit of a CPU hog on > its own, adding the compress/encrypt/decrypt/uncompress overhead is > likely to peg your CPU usage at 100%. Check this while you're running > the backup to confirm. You are either CPU-bound or I/O-bound, and I > suspect it's CPU. CPU bound would be it. Thanks. ___ rdiff-backup-users mailing list at rdiff-backup-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/rdiff-backup-users Wiki URL: http://rdiff-backup.solutionsfirst.com.au/index.php/RdiffBackupWiki
Re: [rdiff-backup-users] slow incrementals over ssh to localhost
On Thu, Mar 08, 2007 at 09:59:20AM -0600, Jeff Strunk wrote: > > I just found that it takes 3 times longer to perform an incremental backup > via > ssh of the local machine than to perform the incremental backup directly. [...] It is most likely due to the CPU overhead of encrypting and decrypting (and possibly compressing/uncompressing) byte of data that needs to be "transferred". In fact, ssh to localhost can be slower than ssh to another on the local network, because the CPU load is split between the two machines. Given that rdiff-backup is a bit of a CPU hog on its own, adding the compress/encrypt/decrypt/uncompress overhead is likely to peg your CPU usage at 100%. Check this while you're running the backup to confirm. You are either CPU-bound or I/O-bound, and I suspect it's CPU. -- Randall ___ rdiff-backup-users mailing list at rdiff-backup-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/rdiff-backup-users Wiki URL: http://rdiff-backup.solutionsfirst.com.au/index.php/RdiffBackupWiki
