RE: [Patch] Optimize dropping of relation buffers using dlist

[tsunakawa.ta...@fujitsu.com]

From: Jamison, Kirk/ジャミソン カーク <k.jami...@fujitsu.com>
compiles. Passes the regression tests too.
> Your feedbacks are definitely welcome.

The code looks correct and has become further compact.  Remains ready for 
committer.


Regards
Takayuki Tsunakawa