how to linking and traversing the inmemory tree

how to linking and traversing the inmemory tree

[siddharth kothari]

hi. 
i am trying to create an in-memory for Reiser4. from
the code i understand the following:
1) Znode is the inmemory representation of the actual
node.
2) children have pointers to thier parents and alsso
maintain their position in parents.
3) Znodes also have the de-limiting keys
and other fields.

now my questions are:

1) from where do you start traversing the tree?
2) are these nodes actually linked in memory as they
are in a tree.
3) once you get a key for a file how do u locate the
lock where the data for that file is to be found.

you obviously compare with the de-limiting keys to get
to the node then wat.... how do u reach any other
level since there are no down pointers.

regards,
siddharth

When I was small I thought everything was either
Black or White,
Good or Bad,
But I grew up to find out everthing was just Grey....


		
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Re: how to linking and traversing the inmemory tree

[Edward Shishkin]

siddharth kothari wrote:

Hello

>hi. 
>i am trying to create an in-memory for Reiser4. from
>the code i understand the following:
>1) Znode is the inmemory representation of the actual
>node.
>2) children have pointers to thier parents and alsso
>maintain their position in parents.
>3) Znodes also have the de-limiting keys
>and other fields.
>
>now my questions are:
>
>1) from where do you start traversing the tree?
>  
>

 From root znode if the node of current position is unknown or got
changed (there is so-called 'seal technique' to understand this),
otherwise traversing is resolved just to per-node lookup.

>2) are these nodes actually linked in memory as they
>are in a tree.
>  
>

Yes, all the relations are the same

>3) once you get a key for a file how do u locate the
>lock where the data for that file is to be found.
>  
>

This is a business of main search procedure (see coord_by_key())

>you obviously compare with the de-limiting keys to get
>to the node then wat.... how do u reach any other
>level since there are no down pointers.
>
>regards,
>siddharth
>
>When I was small I thought everything was either
>Black or White,
>Good or Bad,
>But I grew up to find out everthing was just Grey....
>
>
>		
>__________________________________ 
>Do you Yahoo!? 
>Yahoo! Small Business - Try our new resources site!
>http://smallbusiness.yahoo.com/resources/ 
>
>
>  
>