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How Efficient/Stable are the am-utils?

Posted by Cliff on from the seeking-user-experiences dept.

Steve Baum asks: "I'm thinking of replacing a current tangle of NFS cross-mounted disks with the am-utils system, which maintains a cache of mounted filesystems that are demand-mounted when first referenced and unmounted after a period of inactivity. I was wondering if anyone had used this system in a moderately large (40-50 disks on 10-15 machines) environment and, if so, how efficient and stable they'd found it to be."

2 of 10 comments (clear)

  1. Not very good by Anonymous Coward · · Score: 4, Informative

    I used to use them on my combined network of Sun Ultra2s, Linux-based PCs, and the occasional older SGI. We tried to switch to am-utils to cut down on the network connections and excess traffic created by buggy NFS implementations (eg, those found in Linux kernel-based implementations (the two user-land implementations we later tried were fine, i fogget what either of them is called))

    At any rate, am-utils failed to properly unmount shares on the SGI and Linux machines, which lead to threadlocks on Ultrix and file-descriptor shortages (followed shortly by VM crashes). Needless to say, this was dropped, and we switched to a combination of WebDAV and shared RAID arrays (distributed clustering and NAS systems were also evaluated and later dropped from consideration, mostly due to cost).

    Advice to you? am-utils is not all it seems. Dont forget that NFS is not the only way to get remote file access. Re-evaluate what you need. Sometimes, things as simple as GNOME VFS or Emacs's efs are enough. Otherwise, look at the things I mentioned above.

    -rick

  2. Pretty satisfactory by psmith · · Score: 4, Interesting
    Our environment in my department at Purdue uses am-utils extensively for our NFS handling. Home directories, group file repositories, and shared software installation.

    Am-utils is well suited to what we use it for (or perhaps what we do is determined around what am-utils can do, hmm.) Some examples of what we use it for:

    • Home directories. Home directories come from either of two central fileservers (with the RAID), or if the user's a disk hog, their home directory can be served from their workstation. Amd lets us just forget where something is physically stored and let amd deal with finding /home/psmith. Our group file storage areas work the same way.
    • Shared software installation. Rather than install matlab, OpenPBS, PVM, MPICH, etc. on every system, am-utils lets us install software in a common amd mountpoint, and amd handles the behind-the-scenes stuff to make sure it mounts the version for the proper architecture. Basically, it maps people's requests for /package/matlab to fileserver:/net/fileserver/package/matlab/${os}
    Add in the cross-platform-ness (we mix SunOS, Solaris, FreeBSD, Linux, and AIX in our am-utils environment), and I'm most pleased with it.

    Granted, I'm sure you know of its benefits, but as to its reliability and efficiency, I've got no gripes. Any speed/flakiness issues I've encountered are most likely issues with the underlying NFS implementations, and those have really been pretty few and far between.