[Yum-devel] Sqlite performance + tuning

[seth vidal]

On Wed, 2007-03-21 at 15:39 +0100, Florian Festi wrote:
> > If you have some example code to make the indexes on the fly I'll give
> > it a run on the XO and see how bad it really ends up being.
> 
> Just execute the following SQL statements (terminate with ";" when in the 
> sqlite3 shell)
> 
> CREATE INDEX IF NOT EXISTS pkgprovides ON provides (pkgKey)
> CREATE INDEX IF NOT EXISTS pkgrequires ON requires (pkgKey)
> CREATE INDEX IF NOT EXISTS pkgconflicts ON conflicts (pkgKey)
> CREATE INDEX IF NOT EXISTS pkgobsoletes ON obsoletes (pkgKey)
> 

it's about 15s for fc6 core-only on the XO - a bit long. Moreover it
creates a problem if we make it on the client in that the sqlite db will
no longer match the checksum in the repomd.xml. So we'll be downloading
metadata that isn't, otherwise, needing it. Not much fun, that.

So if we're going to get the advantage from the indexes we need to do
them on the repo side. The only decision now is if the additional speed
is worth the tradeoff of more to download.

-sv