Gateway and Index Store


(optimusprime) #1

I'm not really sure what the difference between the two is. Is the
index store just a caching layer in front of the gateway? Or does the
gateway store only meta-data, and the actual data (JSON) is stored in
the index store? I also read somewhere that when using local gateway,
we need to use a file system store (and not a memory store). Will that
mean that all search operations will read directly from disk?


(Shay Banon) #2

Think of the gateway module as a way to support full restart recoverability.
The local gateway uses the "index store" + additional metadata (stored next
to the index store) in order to recover from a full cluster restart. For
that, you need the index store to be persistent across restarts (file
system). The shared gateway persists the index to a shared storage location,
which all nodes "see".

As for file system, yes, a search will go to the file system, but, its
structured in a way that file system access is optimized (by lucene).

On Wed, Aug 17, 2011 at 11:43 PM, optimusprime usmasood@gmail.com wrote:

I'm not really sure what the difference between the two is. Is the
index store just a caching layer in front of the gateway? Or does the
gateway store only meta-data, and the actual data (JSON) is stored in
the index store? I also read somewhere that when using local gateway,
we need to use a file system store (and not a memory store). Will that
mean that all search operations will read directly from disk?


(system) #3