yum 3.1.4 and repository medata handling

[seth vidal]

On Mon, 2007-03-12 at 04:03 +0530, Rahul Sundaram wrote:
> Hi
> 
> The latest version of yum (3.1.4) in rawhide seems to be behaving rather 
> inconsistently when it comes to dealing with repository metadata. I am 
> cleaning the cache and metadata and rerunning different commands like 
> yum info <package> and yum update to verify.
> 
> On some instances it downloads the compressed sqlite database directly. 
>   In other instances it downloads and parses the compressed xml file. 
> Sometimes it downloads and parses the compressed xml file and then 
> proceeds to download the compressed sqlite database too. It seems to be 
> occurring randomly. Is there any explanation why. I cant see any reason 
> for yum to redundantly download the exact same metadata is the form of 
> both xml file and sqlite database.

are you using a mirror list? It'll download what it can find based on
what mirror list it has.

> 
> Downloading the sqlite database has the advantage that the commands are 
> much more faster (since it skips the "reading metadata" part) but the 
> sqlite database (around 2 MB) also seems to be over the double the size 
> of xml files (800 kb).

not by my measurements. Here is fc6:

-rw-rw-r-- 1 skvidal skvidal 2.4M Feb 20 23:32 filelists.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal 2.4M Feb 20 23:31 filelists.xml.gz
-rw-rw-r-- 1 skvidal skvidal 5.8M Feb 20 23:32 other.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal 6.2M Feb 20 23:31 other.xml.gz
-rw-rw-r-- 1 skvidal skvidal 1.1M Feb 20 23:32 primary.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal 810K Feb 20 23:31 primary.xml.gz


here is FE6:
-rw-rw-r-- 1 skvidal skvidal 4.9M Feb 26 15:35 filelists.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal 4.8M Feb 26 15:35 filelists.xml.gz
-rw-rw-r-- 1 skvidal skvidal 3.8M Feb 26 15:35 other.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal 4.0M Feb 26 15:35 other.xml.gz
-rw-rw-r-- 1 skvidal skvidal 2.9M Feb 26 15:36 primary.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal 2.2M Feb 26 15:35 primary.xml.gz


here are fedora updates for fc6:

-rw-rw-r-- 1 skvidal skvidal  3.0M Feb 26 15:39 filelists.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal  3.2M Feb 26 15:38 filelists.xml.gz
-rw-rw-r-- 1 skvidal skvidal  6.4M Feb 26 15:39 other.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal  7.1M Feb 26 15:38 other.xml.gz
-rw-rw-r-- 1 skvidal skvidal  889K Feb 26 15:39 primary.sqlite.bz2
-rw-rw-r-- 1 skvidal skvidal  653K Feb 26 15:38 primary.xml.gz


not 2x at all.

>  I ran some basic benchmarks with time and Yum 
> 3.1.4 in rawhide is much faster than yum 3.0.3 in FC6 except for the 
> dependency resolving portion.

There are a fair number of other optimizations outside of not parsing
the xml, too.

-sv