Jim Leonard wrote at about 19:45:57 -0500 on Tuesday, August 18, 2009: > Holger Parplies wrote: > > first of all, where are you seeing these figures, and what are you > measuring? > > Rather than try to convince you of my competence, I will offer up these > benchmarks for the exact same endpoint machines and file (a 2 gigabyte > uncompressable *.avi file that did NOT exist on the target): > > Unix rsync->Unix rsync: 60MB/s > Windows SMB->Unix smbclient: 65MB/s > Windows rsyncd->Unix rsync: 5MB/s > Windows rsyncd->BackupPC_dump: 5MB/s > > As you can see, something is now clearly wrong with the windows rsyncd > source. I confirmed this by profiling actual rsync in Unix and saw that > 77% of its time was spent waiting for data (which mirrors exactly what > File::RsyncP::pollsys was doing, wasting 77% of its time waiting for > data). So the problem isn't BackupPC, it's windows rsyncd. > > I initially used cygwin rsync; for the above test, I switched it out for > DeltaCopy's rsync. BOTH VERSIONS had this kind of crappy speed. Both > versions showed hardly any CPU or filesystem usage; they just simply run > slowly for a reason I can't figure out. The network isn't slow (gigabit > ethernet), the checksums aren't taking a long time (it's a brand new > file that doesn't exist on the target so there's nothing to checksum), > the hard drive isn't slow (raid-0 SATA stripe capable of 130GB/s read > speeds) -- it just simply serves data really really slowly. >
I believe that I have noticed similar behavior with rsyncd processes throttled down to near 0% cpu on Windoze machines and backups taking similarly long. > I can't believe this is an isolated incident. Other people have got to > be seeing this. Other than cygwin and DeltaCopy, is there any specific > version of rsyncd I should be using? Any flags I can set in BackupPC > that can improve speed? > > > The primary purpose of the rsync protocol is to save network > bandwidth. So if, > > for example, you are transferring only one tenth the amount of data > for a full > > backup, and that takes the same time as with SMB, your network > throughput will > > These are not incrementals, but full backups, and the speed as > previously mentioned is 1/10th that of SMB. SMB backups are quite fast > on this same infrastructure (around 65MB/s) but I can't use SMB because > of XP/Vista/Win7 permission problems. > > > I believe Craig is researching other alternatives (a fuse FS to handle > > compression and deduplication, so BackupPC could, in fact, use native > rsync). > > I hope that doesn't become mandatory, because that would limit BackupPC > to Unix versions that support FUSE (not all do). > -- > Jim Leonard (trix...@oldskool.org) http://www.oldskool.org/ > Help our electronic games project: http://www.mobygames.com/ > Or check out some trippy MindCandy at http://www.mindcandydvd.com/ > A child borne of the home computer wars: http://trixter.wordpress.com/ > > ------------------------------------------------------------------------------ > Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day > trial. Simplify your report design, integration and deployment - and focus > on > what you do best, core application coding. Discover what's new with > Crystal Reports now. http://p.sf.net/sfu/bobj-july > _______________________________________________ > BackupPC-users mailing list > BackupPC-users@lists.sourceforge.net > List: https://lists.sourceforge.net/lists/listinfo/backuppc-users > Wiki: http://backuppc.wiki.sourceforge.net > Project: http://backuppc.sourceforge.net/ > ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/