A Dimecres 28 Maig 2008, Dave Howorth va escriure: > Leopold Palomo-Avellaneda wrote: > > A Dimecres 28 Maig 2008, Dave Howorth va escriure: > > > > The icy box _only_ offer network connection. So, maybe one option should > > be use another box (with a Linux) and this external hd connected via nfs. > > Then I could have a bot with ram and cpu to run rsync. But, by now, I > > couldn't. > > Well, that still leaves the NFS link as a performance killer. If the icy > box can't be upgraded then the best solution (but maybe not achievable) > might be to remove the disk(s) from it and connect them to another > computer.
:-( ok, I take note. > > >> As it is, it looks like most time is spent transferring files, since > >> your logs say "File list generation time: 882.634 seconds" and "File > >> list generation time: 927.970 seconds" which is only 15 mins if my > >> arithmetic is correct. Even the total bytes transferred is only 90 MB or > >> so. Which points to NFS speed as the main suspect, IMHO. > > > > yes, I agree, but let me show you some numbers. > > > > I have a directory with dumps of svn. The directory has a size of: > > ris:/opt/backup# du -sh /srv/seg/repositori/ > > 3,5G /srv/seg/repositori/ > > ris:/opt/backup# du -s /srv/seg/repositori/ > > 3590972 /srv/seg/repositori/ > > > > if I do I simple copy of the whole directory to the nfs unit, I got: > > > > ris:/opt/backup# time cp -r /srv/seg/repositori /opt/backup/test/ > > > > real 18m26.502s > > user 0m0.148s > > sys 0m6.532s > > > > so, it has needed 18m and 26.502 s to copy 3.5G. So, making some > > division: 3590972/(18*60 + 27) = 3243.8 ~ 3.5 Mb/s > > I agree, except that's 3.5 MB/s isn't it, which makes about 28 Mb/s. > That's believable for a 100 Mbit link, but you said you had a 1 Gbit link? yes, and I physically have been to the servers room and looked the switch and the cables. And I did an error in the units. In the icy box there's a raid1, but I don't think that could affect. > So the first performance problem appears to have nothing to do with > rsync; it's simply that your network is running slow. Are you absolutely > sure it is running at 1 Gb and hasn't downspeeded for some reason? I > think you need to run some network diagnostics. well I can investigate ... > (that's assuming you can actually better that rate on local disk > transfers :) > > >> As far as I can see, you haven't posted your NFS export and mount > >> settings, nor any measurement of actual network transmission rates. > > > > the server mounts the nfs unit with: > > ulises:/mnt/md1/backup /opt/backup nfs > > rsize=32k,wsize=32k,intr,rw,nfsvers=3,retrans=10 0 0 > > > > and the icy box export the unit: > > > > /mnt/md1/backup X.Y.Z.K(rw,no_root_squash,sync) > > I think others have suggested using noatime; that will definitely help. > I believe that using sync will also slow it down but I haven't tried > that recently. well is more secure. Proving the noatime at mount, I got: ris:/opt/backup# time cp -r /srv/seg/repositori /opt/backup/test/ real 18m12.526s user 0m0.172s sys 0m6.452s a 2% more faster ... How can I test the network with this box? I cannot run the iperf because I need to run it in the icy box and it's not possible. Maybe, compiling it using crosscomplie, etc .... Regards, Leo _______________________________________________ Dirvish mailing list [email protected] http://www.dirvish.org/mailman/listinfo/dirvish
