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. >> 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? 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. (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. Cheers, Dave _______________________________________________ Dirvish mailing list [email protected] http://www.dirvish.org/mailman/listinfo/dirvish
