> According to the postgres research papers, the no-overwrite storage
> manager has the following attributes...

But don't forget about conclusion they made...

> * It's always faster than WAL in the presence of stable main memory.
> (Whether the stable caches in modern disk drives is an approximation I
> don't know).

And much slower in the absence...

> * It's more scalable and has less logging contention. This allows
> greater scalablility in the presence of multiple processors.

We can implement multiple log files (on different disks) someday.
The only contention will be for reading/changing some number
(required for recoverer to read logs in right order)...

> * Instantaneous crash recovery.

And slow vacuum...

> * Time travel is available at no cost.

We told about that already.

> * Easier to code and prove correctness. (I used to work for a database
> company that implemented WAL, and it took them a large number of years
> before they supposedly corrected every bug and crash condition on
> recovery).

The only plus for me -:)

Vadim

Tue, 11 Jul 2000 11:49:06 -0700
"Mikheev, Vadim" <vmikheev@SECTORBASE.COM>
RE: Storage Manager (was postgres 7.2 features.)