On Mon, Nov 4, 2013 at 11:32 AM, Andres Freund <and...@2ndquadrant.com> wrote:
> I think doing this outside of s_b will make stuff rather hard for
> physical replication and crash recovery since we either will need to
> flush the whole buffer at checkpoints - which is hard since the
> checkpointer doesn't work inside individual databases - or we need to
> persist the in-memory buffer across restart which also sucks.

You might be right, but I think part of the value of LSM-trees is that
the in-memory portion of the data structure is supposed to be able to
be optimized for in-memory storage rather than on disk storage.  It
may be that block-structuring that data bleeds away much of the
performance benefit.  Of course, I'm talking out of my rear end here:
I don't really have a clue how these algorithms are supposed to work.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


-- 
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers

Reply via email to