[mkgmap-dev] Splitter --cache parameter

Sun Aug 23 19:54:44 BST 2009

Chris Miller a écrit :

Hi Chris,

> If you want to enable the disk caching, you specify the cache location as 
> follows:
> 
> --cache=<directory>
> The --cache parameter is entirely optional. if you don't specify it, the 
> splitter will work in exactly the same way it did previously.
> 
> I hope the above explanation makes sense. Any questions, comments or suggestions 
> are welcome.

I'm testing it against Switzerland.

1st run : With the option --cache enable, these are the results :

20h 20mns 17s - On va decouper la carte switzerland.osm.bz2 en plusieurs
morceaux (beginning)
20h 23mns 35s - On a fini le decoupage de la carte switzerland.osm.bz2.
(end)
(local time)

2nd run : Same as 1st run, so --cache enable, but I've not removed the
previously created node.xxx, ways.xxxx and relations.xxxx files created.
-rw-r--r--  1 fm users     8200 2009-08-23 20:22 nodes.bin.keys
-rw-r--r--  1 fm users 69494780 2009-08-23 20:22 nodes.bin
-rw-r--r--  1 fm users     6481 2009-08-23 20:22 ways.bin.keys
-rw-r--r--  1 fm users 25194598 2009-08-23 20:22 ways.bin
-rw-r--r--  1 fm users     1312 2009-08-23 20:22 relations.bin.roles
-rw-r--r--  1 fm users     1693 2009-08-23 20:22 relations.bin.keys
-rw-r--r--  1 fm users   474197 2009-08-23 20:22 relations.bin

For that same run, it gives me :
20h 28mns 08s - On va decouper la carte switzerland.osm.bz2 en plusieurs
morceaux (begin)
20h 29mns 05s - On a fini le decoupage de la carte switzerland.osm.bz2.
(end)

Problem : it doesn't want to write new nodes.xxxx etc... files. The
files are the same as before. It seems that splitter sees the already
created files, and doesn't want to create new one by overwritting the
previous ones. This gave me a problem, as I run splitter first against
Andorra ( ;-) very tiny osm file), and then after against Switzerland.
Splitter used the nodes.xxx ways... and relations.xxx files created for
Andorra.

3rd run : without the option --cache enable :
20h 35mns 33s - On va decouper la carte switzerland.osm.bz2 en plusieurs
morceaux
20h 39mns 51s - On a fini le decoupage de la carte switzerland.osm.bz2.

So it much faster.

Francois

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