Re: [Monotone-devel] Server broken
On Sun, Oct 11, 2009 at 01:20:38PM -0400, Ethan Blanton wrote: > It should probably be clarified that John's experience includes > serving monotone, specifically. Pidgin and its related projects have > had monotone on a number of virtual servers from varying providers > over the years, and our experiences have been Really Bad. Monotone is > extremely demanding of I/O in a way which virtual hosts seem to have a > lot of trouble with. Ah, yes -- pidgin is probably a much more demanding user of monotone than I am. I haven't had any problems running a monotone server with a ~300 Mb database on my vm, but it sees maybe a 100 connections a day, so probably not really a similiar experience. -Jack ___ Monotone-devel mailing list Monotone-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/monotone-devel
Re: [Monotone-devel] Server broken
Jack Lloyd spake unto us the following wisdom: > On Sat, Oct 10, 2009 at 11:51:19AM -0400, John Bailey wrote: > > Virtual machines, especially those provided by OpenVZ and Virtuozzo, > > are not the greatest things in the world--the seller can overcommit > > the physical hosts or the hosts can be under-powered, and any one > > virtual machine can flood disk I/O out to the point that it kills I/O > > performance for other VM's and the other VM's can never tell why. > > These factors result in the VM being unacceptably slow, especially in > > disk I/O--this makes IMAP extremely slow to respond and can make even > > simple shell work unbearably slow. I've seen this particular problem > > on every Virtuozzo or OpenVZ VM I've ever had access to. > > Really this just depends on the provider, though. I've been using an > OpenVZ instance as my web/mail/shell server for ~3 years and it's been > great for me. (The provider I'm with is a bit pricier than most, OTOH > - though still way cheaper than a dedicated box). It should probably be clarified that John's experience includes serving monotone, specifically. Pidgin and its related projects have had monotone on a number of virtual servers from varying providers over the years, and our experiences have been Really Bad. Monotone is extremely demanding of I/O in a way which virtual hosts seem to have a lot of trouble with. Of course, proper provisioning *will* go a long way toward fixing this problem. Ethan -- The laws that forbid the carrying of arms are laws [that have no remedy for evils]. They disarm only those who are neither inclined nor determined to commit crimes. -- Cesare Beccaria, "On Crimes and Punishments", 1764 signature.asc Description: Digital signature ___ Monotone-devel mailing list Monotone-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/monotone-devel
Re: [Monotone-devel] Server broken
On Sat, Oct 10, 2009 at 11:51:19AM -0400, John Bailey wrote: > Virtual machines, especially those provided by OpenVZ and Virtuozzo, are not > the > greatest things in the world--the seller can overcommit the physical hosts or > the hosts can be under-powered, and any one virtual machine can flood disk I/O > out to the point that it kills I/O performance for other VM's and the other > VM's > can never tell why. These factors result in the VM being unacceptably slow, > especially in disk I/O--this makes IMAP extremely slow to respond and can make > even simple shell work unbearably slow. I've seen this particular problem on > every Virtuozzo or OpenVZ VM I've ever had access to. Really this just depends on the provider, though. I've been using an OpenVZ instance as my web/mail/shell server for ~3 years and it's been great for me. (The provider I'm with is a bit pricier than most, OTOH - though still way cheaper than a dedicated box). -Jack ___ Monotone-devel mailing list Monotone-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/monotone-devel
Re: [Monotone-devel] Server broken
Ludovic Brenta wrote: > Since this server is mission-critical (its missions being to serve > monotone databases and your email), how about migrating to serious > server hardware with RAID storage? Thanks to virtual machines, this can > be as inexpensive as a dedicated server, e.g. Virtual machines, especially those provided by OpenVZ and Virtuozzo, are not the greatest things in the world--the seller can overcommit the physical hosts or the hosts can be under-powered, and any one virtual machine can flood disk I/O out to the point that it kills I/O performance for other VM's and the other VM's can never tell why. These factors result in the VM being unacceptably slow, especially in disk I/O--this makes IMAP extremely slow to respond and can make even simple shell work unbearably slow. I've seen this particular problem on every Virtuozzo or OpenVZ VM I've ever had access to. I would avoid virtual machines at all costs. John signature.asc Description: OpenPGP digital signature ___ Monotone-devel mailing list Monotone-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/monotone-devel
Re: [Monotone-devel] Server broken
On Sat, Oct 10, 2009 at 12:08:10PM +0200, Ludovic Brenta wrote: > Richard Levitte writes: > > What I'll do next is to move the server home within the week that > > comes [...], check things through, copy what can be copied to the > > spare disk, take the rest from backups (the backup is good), move > > disks around and take it back to co-location, then cross my fingers. > > Since this server is mission-critical (its missions being to serve > monotone databases and your email), how about migrating to serious > server hardware with RAID storage? Thanks to virtual machines, this can > be as inexpensive as a dedicated server, e.g. > > http://wiki.openvz.org/Hosting_providers > http://linux-vserver.org/VServer_Hosting > Isn't there already http://mtn-host.prjek.net/projects/monotone/ ? It doesn's present a nice web page, or Richard's email, but the monotone repository is there, isn't it? -- hendrik ___ Monotone-devel mailing list Monotone-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/monotone-devel
Re: [Monotone-devel] Server broken
Richard Levitte writes: > What I'll do next is to move the server home within the week that > comes [...], check things through, copy what can be copied to the > spare disk, take the rest from backups (the backup is good), move > disks around and take it back to co-location, then cross my fingers. Since this server is mission-critical (its missions being to serve monotone databases and your email), how about migrating to serious server hardware with RAID storage? Thanks to virtual machines, this can be as inexpensive as a dedicated server, e.g. http://wiki.openvz.org/Hosting_providers http://linux-vserver.org/VServer_Hosting -- Ludovic Brenta. ___ Monotone-devel mailing list Monotone-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/monotone-devel
[Monotone-devel] Server broken
I'll admit, this is starting to be tiresome. My server has been a tad problematic lately, and it's getting there again. This time, the disk has broken in a pretty serious way. Lots of file names seem to be disconnected from their inodes, giving me listings like this: # ls -l /var/log ... -? ? ?? ?? syslog.4.gz That's not something that makes me joyful. I have a spare disk, same brand and model. I can only hope that the current disk was some kind of extreme and that it doesn't speak for that brand or model. What I'll do next is to move the server home within the week that comes (in the little time that I have, this had to happen right before a busy week, didn't it, eh Murphy? ;-)), check things through, copy what can be copied to the spare disk, take the rest from backups (the backup is good), move disks around and take it back to co-location, then cross my fingers. All this makes me think that this could be a good reason to pick up an idea that I recall was mentioned here before, a way to have a number of machines cooperating in some kind of loose monotone cluster. As it is now, I'm reachable on this address. My server may be up, but my imap folder is partly trash, making it difficult to do something useful with it. -- Richard Levitte ___ Monotone-devel mailing list Monotone-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/monotone-devel
