Hi Christian,
Thanks for your response.
On Mon, Mar 24, 2014 at 10:34 PM, Christian Grün christian.gruen@gmail.comwrote:
Hi Ying,
I am just very curious why for read-only queries, they will compete for
disk
I/O.
The reason is that your query requires a sequential scan of the full XML structure. If you run several requests in parallel, all requests will try to read the same blocks in a slightly delayed order. As a result, the pointer, which is reading a block on disk, will be moved again and again, and the resulting pattern is somewhat random.
It there anyway we can brutely load the whole index and then do the
queries.
Due to the nature of your query, there is now way to benefit from index structures. Instead, I would suggest to create additional databases that contain all the information you will be frequently accessing.
Christian