Re: What happens with the indexed directory patch ?

Theodore Ts'o
2002-09-06T10:45:33Z

On Thu, Sep 05, 2002 at 05:59:09PM +0200, Carles Xavier Munyoz Bald?
wrote:
>
> Please, help me. I believe that the htree indexed directory is a very very
> great improvement for the ext2/ext3 file system that must become a standard
> as soon  as possible.

I'm not sure why you're not seeing the improvement based on the Daniel
Phillip's ext2 patch (it worked for me) but let me give you an updated
set of patches and a test script for ext3.

I'm still working on cleaning it up, and the version I'm sending you
still is missing some error checks and doesn't have the code cleanup
that is still on-going, but it's been slightly better tested than the
most bleeding edge code that I have.  (Translation: I've tested it for
two hours in my hotel room in Koeln, after I got back from the Linux
Kongress Social.  So **please** don't run this on a production system,
at least not until you've done your own testing and validation.)

(To Andreas: I've done the work to make the code support multiple hash
algorithms, so we can now smoothly transition between filesystems that
were running Daniel Phillip's original dx_hack_hash and the latest
format as supported by this patch and e2fsprogs 1.28).

Using this patch, it is very easy to demonstrate that if you don't
turn on the indexed directory filesystem feature, the test scripts
take a **lot** longer.  With the indexed directory feature turned on,
running the script only takes about 3 minutes of real time on my
laptop, and the disk drive light was on most of the time.  With the
indexed directory feature turned off, running the script took over 15
minutes and had only completed a tiny fraction of the directory
entries before I gave up and hit Control-C.  So you should an
orders-of-magnitude improvement with the indexed directory feature
turned on.

Caveats: This patch and the test script requires the use of e2fsprogs
1.28.  Also, the mke2fs options in the test script are designed to
stress the htree code using a minimal amount of disk space on my
laptop.  They should not be used for production filesystems.  Finally,
the debugfs commands to initialize the filesystem will be
automatically done by mke2fs in the next release of e2fsprogs.

So rest assured, we *are* working on the htree indexed directory code.
I fully intend for this to get integrated into the 2.5 tree, even if
we don't have the NFS readdir fixes done at first.

						- Ted