keys /metadata only in memory permanently (not swapped out) & data in disk
Please let me know your expert opinion !
This is my post to another group ,
Does any one know if couchbase would keep only the keys in the memory as opposed to the entire data (and let demand paging /swap decide what should be in the memory or not).
If we have only keys in the memory ,if the searches we are doing in the database would only give one record out and the search keys are random then having only keys in the memory would make optimal use of memory i,e could load it once and have it in RAM for ever and use the key to get to the data location .
I we have entire data in memory then OS demand paging would be a performance hit on the system .
Please let me know if couchbase works the above way i am looking for .
Thank in advance
And i got a response from someone :
Couchbase Server ( http://www.couchbase.com ) is using this approach (all keys and metadata are in memory) and the data (JSON Document or generic content) are loaded in memory when needed (accessed).
Here some interesting reading about Couchbase Architecture:
- Couchbase Architecture : http://www.couchbase.com/docs/couchbase-manual-2.0/couchbase-architectur...
- Detailed Blog: http://horicky.blogspot.fr/2012/07/couchbase-architecture.html
Could you please double confirm that the couchbase keeps keys &metadata only in memory/cache and the data/documents are loaded into memory only when they are accessed , this way we can optimize RAM usage .
Please let me know your expert opinion .