On Fri, Jun 06, 2008 at 07:24:20PM +0200, Frederik Ramm wrote: > Hi, > > > The advantage is that writing articles to a storage means only appending > > or linear overwriting of the containers storage and expiring the old > > locations. Thing about a log structured filesystems. > > I don't understand this argument. You argue that filesystems cannot > be trusted to do efficiently what they were designed to do, and that > we would be better of coding something of our on on top?
Yep - most filesystems are written to be multipurpose. To have a mix of
large and small files as in your homedirectory. Having thousands or
millions of small files in one or thousands of directory
is not a topic which filesystems get optimized for.
> It won't be long and you'll tell us to return to the design we had
> two years ago where the PNG data was contained in blobs in the
> database, on the grounds that the database is more efficient in
> retrieving these blobs from its one huge storage file than the
> filesystem can serve tiles ;-)
A database is optimized to a very different end. Typically the data you
retrieve is small and the working set you are workin on is huge read -
larger than your main memory. So the database optimizes the amount of
data to read/touch by having clever indexes and query planner. Just
retrieving a predefined chunk of data and using the database only for
its index and data layout is adding overhead.
Flo
--
Florian Lohoff [EMAIL PROTECTED] +49-171-2280134
Those who would give up a little freedom to get a little
security shall soon have neither - Benjamin Franklin
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