Hi, Check your storage config file here:
/etc/pve/storage.cfg Modify (add) your preferred switches to your nfs mount options. You can search the forum (or google) for examples if you are unsure. I hope it solves your problem :) Bye, István ----------------eredeti üzenet----------------- Feladó: "Chris Murray" [email protected] Címzett: "Pongrácz István" , "Alexandre DERUMIER" [email protected] CC: "pve-user pve.proxmox.com" Dátum: Tue, 4 Feb 2014 16:01:58 -0000 ------------------------------------------------- > Ah-ha, that would certainly explain what I'm seeing. Thank you István! :-) > > Can anyone comment on how or where I can slip extra mount options into the > proxmox > hosts? I notice my /etc/fstab doesn't list the NFS mounts. > > Also, would there be any mileage in documentation warning that the > "writethrough" option won't operate as expected if the underlying storage is > over NFS? > > Cheers, > Chris > > -----Original Message----- > From: Pongrácz István [mailto:[email protected] ] > Sent: 04 February 2014 15:31 > To: Chris Murray; Alexandre DERUMIER > Cc: pve-user pve.proxmox.com > Subject: RE: [PVE-User] Understanding write caching in proxmox > > You should: > - force your server to export in sync mode > - force your client to mount in sync mode > > From the nfs manpage: > > The NFS client treats the sync mount option differently than some other file > systems (refer to mount(8) for a description of the generic sync and async > mount > options). If neither sync nor async is specified (or if the async option is > specified), the NFS client delays sending application writes to the server > until any of these events occur: > > Memory pressure forces reclamation of system memory resources. > An application flushes file data explicitly with sync(2), msync(2), or > fsync(3). > An application closes a file with close(2). > The file is locked/unlocked via fcntl(2). > > In other words, under normal circumstances, data written by an application > may > not immediately appear on the server that hosts the file. > > If the sync option is specified on a mount point, any system call that writes > data > to files on that mount point causes that data to be flushed to the server > before the > system call returns control to user space. This provides greater data cache > coherence among clients, but at a significant performance cost. > > Good luck! > > > ----------------eredeti üzenet----------------- > Feladó: "Chris Murray" [email protected] > Címzett: "Pongrácz István" > , "Alexandre DERUMIER" [email protected] > CC: "pve-user pve.proxmox.com" > Dátum: Tue, 4 Feb 2014 14:58:06 -0000 > ------------------------------------------------- > > >> I'm not sure I get a chance to specify? >> >> root@pm02 :/# mount -l | grep 231 >> 192.168.0.231:/mnt/foxpool on /mnt/pve/foxpool type nfs >> >> (rw,relatime,vers=3,rsize=65536,wsize=65536,namlen=255,hard,proto= >> tc >> >> p,timeo=600,retrans=2,sec=sys,mountaddr=192.168.0.231,mountvers=3, >> mo >> untport=918,mountproto=udp,local_lock=none,addr=192.168.0.231) >> >> It was set up using the web interface, where I can't see an option for this. >> >> NFS client certainly feels asynchronous to me. Suppose I "sar -n DEV 1 | >> grep >> eth0" >> while I observe this 'buffering' effect ... I see next to no activity until >> the >> >> instant that "zpool iostat" does. i.e. the proxmox host is holding onto data >> and >> choosing to flush it at a later stage. >> >> Thanks again, >> Chris >> >> -----Original Message----- >> From: Pongrácz István [mailto:[email protected] ] >> Sent: 04 February 2014 14:39 >> To: Chris Murray; Alexandre DERUMIER >> Cc: pve-user pve.proxmox.com >> Subject: Re: [PVE-User] Understanding write caching in proxmox >> >> >> How about your NFS setup? Sync, async? >> >> István >> >> ----------------eredeti üzenet----------------- >> Feladó: "Chris Murray" [email protected] >> Címzett: "Alexandre DERUMIER" [email protected] >> CC: [email protected] >> Dátum: Tue, 4 Feb 2014 14:14:51 -0000 >> ------------------------------------------------- >> >> >>> Sorry, I might have misled you with my question. It might have the >>> appearance of another general and possibly quite common one. >>> >>> My troubleshooting was performed on the proxmox *host*, therefore I >>> was under the impression that cache=[whatever] wouldn't make a >>> difference since that's a property of a virtual machine disk. >>> >>> For the *VM*, I'm using writethrough .. however I'm observing exactly >>> what you explained for 'none' or 'writeback'. My VM is Windows Server >>> 2008 R2, and I'm using sdelete to fill it with data. 'sdelete -z' >>> won't appear on the 'zpool iostat' for quite some time, while the >>> cached figure on the proxmox host increases. That's despite the disk >>> being >>> set to writethrough. >>> >>> Apologies if I'm not being clear. >>> >> >> >> >> ----- >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2014.0.4259 / Virus Database: 3684/7058 - Release Date: 02/03/14 >> > > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2014.0.4259 / Virus Database: 3684/7058 - Release Date: 02/03/14 > _______________________________________________ pve-user mailing list [email protected] http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-user
