[lkml]   [1999]   [Mar]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: multiply files in one (was GNU/Linux stance by Richard Stallman)
    : > If you have 200 small files and you have to go get 200 inodes and
    : > 200 blocks to read them in, the inodes and the blocks aren't next to
    : > each other, that's 400 disk transactions instead of 1.
    : OK, so please explain the scale of what you have in mind. How big is
    : the compressed tarball, and how big is it uncompressed?
    : Do you plan on having a large FS (say /usr) stored in this way, or are
    : you thinking of a selected subset?

    Do it on a per directory basis, only for files where links == 1.

    I wouldn't bother to compress - just putting all the files into a ``tarball''
    will compress them quite nicely because of the lack of fragmentation.
    Compression isn't the point, disk access / file read is the point. For a
    large group of small files I want 2 disk accesses (inode + tarball) for all
    files, instead of 2/file.

    : Note that I'm thinking about reading-ahead the inodes *and* the
    : blocks. If you have RAM to burn, then this looks like it should
    : work. I'm not thinking in terms of reading ahead a few piddling
    : blocks. I'm talking megabytes or dozens of megabytes.
    : So with two seek operations, you can read-ahead lots of files and lots
    : of data.

    More brain cells, more, more, more, I want more. :-)

    It's a transaction cost, not a platter speed cost. Read ahead does not
    help you on small files and inodes.

    Look, if things worked the way I'm describing then you should see a
    quantum leap in small file performance. Think 10x faster and you'll
    see that the number of I/O's have to go down by at least a factor of 10.

    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:51    [W:0.021 / U:5.128 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site