On Thu, 5 Apr 2007 03:34:50 -0500 "Rob Sanheim" <[EMAIL PROTECTED]> wrote:
> > So for page caching across a cluster, or static resources in general > w/ a rails cluster, is NFS a bad idea? I've read a lot of posts where > folks talk about how unreliable NFS has been in the past, and it has > issues with locking and what not. My company has had issues as well > when servers are restarted and have issues reconnecting to the NFS > mount. In most of the cases I've seen people using NFS they tend to run into problems either with reliability or with overloading traffic. On the reliability end, they expect NFS to work transactionally for reads and writes of entire files, or expect the locks to work flawlessly. With overloading traffic it seems they expect NFS to take less traffic than HTTP (partially true) but then slam tons of file reads/writes over NFS and HTTP at the same time. In some cases I've seen people effectively send the contents of a file 3-4 times over the network for each single HTTP request. I'm sure other people could chime in with their setups, but the only configuration I've seen work reasonably well is the following: 1) Setup a "static server" that has an NFS mountable and writable directory. 2) This static server then has a fast as hell HTTP server (nginx works well) that reads the files in this mountable directory straight off the disk NOT OFF NFS. 3) All of the rails backends then write to the NFS mount to put the asset onto the static server, and write their URLs to point at this new static asset URL instead of the rails URL or do a redirect. This works best for assets that you can classify and which aren't going to change often. The key is that you've written the asset fully BEFORE you send the response that the client uses to read the asset. If you try to do it in parallel then the client could end up reading a partially written asset. There's also problems with this NFS usage potentially stopping a Mongrel server if NFS has problems writing the file. I actually don't advise NFS, so you can also try other options like Samba, Lustre, CODA, etc. -- Zed A. Shaw, MUDCRAP-CE Master Black Belt Sifu http://www.zedshaw.com/ http://www.awprofessional.com/title/0321483502 -- The Mongrel Book http://mongrel.rubyforge.org/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Deploying Rails" group. To post to this group, send email to rubyonrails-deployment@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/rubyonrails-deployment?hl=en -~----------~----~----~----~------~----~------~--~---
