Re: Some more questions about Reiser4 ;)

["Fred -- Speed Up --" <speedup@free.fr>]

Thank you for your answers ;)

You're right, I'd have to read the source code, but I don't really know
where I can find it : where do you keep the recent snapshots, the only thing
I've been able to download is your 2.5.60 patch and the february Reiser4
utilities.

> Until fsck is done, filesystem cannot be used in production anyway :) We
> working on fsck now and another tools. If you are intersting, I will
> send you package or link, it may obtained at.
It would be nice if you could sent me the url, thank you ;)

> The parsing the file path is fully VFS' job.
Probably ... but the Reiser4 doc specifies a "semantic layer" and a "storage
layer" : does the semantic layer only consist in VFS resolving path from
standard Reiser4 directory reading methods based on reading directory
entries and everytime resolving the whole path reading the Reiser4 physical
tree ?
Does Reiser4 implement some new ways of resolving paths, as I thought I've
read in the doc, to convert file paths to keys or does VFS alone achieve
this ?
When you're speaking of a graph used by the semantic layer, would it be part
of the VFS caching process ?
Another thing I could hardly understand : does Reiser4 keep directories
apart from files so that path can be cached or are they kept with the same
status normal files got ?

> We should understand the difference between balancing and keeping tree
> consistent.
> Tree is consistent if the following rule is hold true: all nodes may be
> accessed by means of using theirs left delimiting keys.
> Tree is balanced if all used invariants are hold true (for instance, all
> nodes are half filled, or all nodes fully filled, etc). Also tree should
> not be singular.
>
> Reiser4 in balancing time (any tree modification) does only care about
> tree consistency and keeps it in not singular state. Whereas flush does
> care about invariants (packing, etc).
I didn't noticed the difference, thank you for pointing this out. I
understand the "balancing" process, which is documented on your website,
meaning packing dirty memory items on flushing, but I don't understand what
you mean by "tree should not be singular" : does this mean a twig should
contain more than one item ?
The really interesting thing (the mysterious one :-D) is the
consistency-keeping process. I didn't really understood the left-delimiting
key concept, I guess it's something like a path in the storage tree, am I
right ? In a consistent tree, do all the inodes got the same left-delimiting
key depth ?


Real thank you for your answers Yuri ;)
I'm going to read my "kernel internals" book to know more about the VFS and
ext2 handlings, so you can expect some more questions (or answers ;))
comming :-D

Fred