On 02/03/2011 13:05, Bruno Rohée wrote:
On Wed, Mar 2, 2011 at 12:33 PM, Rob Pettefar
<[email protected]> wrote:
Hi guys
I've got a question about improving the speed at which views are updated in
our system:
Currently we use a set of database documents to make up whole files after
they have been requested out of the system. When submitted back into the
database the old docs that held data are deleted and new docs are created in
their place. This was done for simplicity of design. However when we have
large file submitted into the system this will involve the deletion and
creation of a large number of docs being deleted and created (we are looking
at around 4,000 deletes and 4,000 new docs).
The views then take some time to update after this has happened.
If we were to instead, modify the contents of the 4,000 documents (perhaps
with some deletions and creations) would this reduce the amount of updates
the system would have to put though the views and thus, reduce the time
needed to update the views?
I think it's pretty dependent on your data, whether your new documents
are mostly identical or mostly different from the old ones. If it's
the former the process can be sped up quite a bit as the map function
will only be called on the changed documents, if it's the later not
much speed gain to be expected IMHO.
This would probably involved writing over the content of the document,
even with the same data as before, inuring a new revision number. I
guess that this would cause the map functions to be run over it again.
However I think the key thing here is a question of how mass deletions
are treated by the view updater.
