Lustre has its own load-balancing algorithms (either round-robin or weighted) depending on the space usage of the OSTs.
在 2010-12-16，下午11:25， Eudes PHILIPPE 写道： > I was wrong about what I say > If oss1 and 2 are full, oss3 is ok, and if I sent a new file, upload is ok > (sftp said nothing), but the file is different (the md5sum si different!) > It's very dangerous!! > > Is there a solution, if I see all ossX are almost full, when I add (some) new > oss, distribute data on these new oss to always have the same poucentage use > on all oss? > > > > -----Message d'origine----- > De : Wang Yibin [mailto:[email protected]] > Envoyé : jeudi 16 décembre 2010 16:09 > À : Eudes PHILIPPE > Cc : lustre-discuss > Objet : Re: [Lustre-discuss] howto make a lvm, or virtual lvm? > > > 在 2010-12-16，下午10:49， Eudes PHILIPPE 写道： > >> Ok, so, i'll try this : >> - One mds >> - 2 physical oss with one drive (1 GB) (one ost on one oss) >> >> On client, mount mds on /home.. >> lfs setstripe -c2 /home >> >> I upload (in sftp) one file, 300 MB >> - On Oss 1, he use 150 Mb of 1000 >> - On Oss 2, he use 150 Mb of 1000 >> >> All right! >> >> I continue... copy my first file 4 times (so there is 5 * 300 MB = >> 1500 MB) >> - On Oss 1, he use 750 Mb of 1000 >> - On Oss 2, he use 750 Mb of 1000 >> >> ************************* >> Now, I add a new oss server, with one ost (1GB) >> - On Oss 1, he use 750 Mb of 1000 >> - On Oss 2, he use 750 Mb of 1000 >> - On Oss 3, he use 0 Mb of 1000 >> >> lfs setstripe -c3 /home on client >> >> I upload a big file, 1.3 Go >> He write on oss1, 2 and 3, but, when oss 1 and oss2 are full, he stop >> (Couldn't write to remote file "/home/big_log.log": Failure) >> ****************************** > > All files in a directory inherits its parent dir's stripe attributes. > As you set the mountpoint dir to stripe over 3 OSTs, all files in it will be > written to 3 objects located in different OSTs. > As OST 1 and 2 are full, surely you'll get write failure with ENOSPC. > >> >> So now, >> - On Oss 1, he use 1000 Mb of 1000 >> - On Oss 2, he use 1000 Mb of 1000 >> - On Oss 3, he use 250 Mb of 1000 >> I upload again, just for see, my first file (300 MB), he copy the file >> only on Oss3 (oss 1 and 2 are full of course), it's ok :) >> >> Is there a solution for this problem? > > If you want to do write with system that has full OSTs, you need to either 1) > deactivate the full OSTs, or 2) set stripe size and offset properly. > In your specific case, get the stripe size of your file to 1 and stripe > offset to 2 (assuming the non-full OST index is 2). > >> >> Regards >> >> >> >> -----Message d'origine----- >> De : Andreas Dilger [mailto:[email protected]] >> Envoyé : mercredi 15 décembre 2010 22:39 À : Eudes PHILIPPE Cc : >> [email protected] Objet : Re: [Lustre-discuss] howto >> make a lvm, or virtual lvm? >> >> On 2010-12-15, at 10:06, Eudes PHILIPPE wrote: >>> At the end, I want (if it's possible), a raid 5 over Ethernet, or, 1 >> physical raid 5 on each ostX and a big lvm I can extend as I want.... >> >> Lustre itself can not do RAID over the network, if that is what you >> are looking for... >> >>> For my first test, I upload on client a file (1.8 Go) (each ost have >>> 1 >>> Go) The problem, is, when sdb is full, he stop the copy, and don't >>> continue on ost2 >> >> If you create your file to be striped over both OSTs, then it should work. >> >> Use "lfs setstripe -c2 /home/newfile" to specify a stripe count of 2. >> >> Cheers, Andreas >> -- >> Andreas Dilger >> Lustre Technical Lead >> Oracle Corporation Canada Inc. >> >> >> _______________________________________________ >> Lustre-discuss mailing list >> [email protected] >> http://lists.lustre.org/mailman/listinfo/lustre-discuss > > > _______________________________________________ > Lustre-discuss mailing list > [email protected] > http://lists.lustre.org/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
