Re: dynamically allocating chunks from shared memory

Markus Wanner <markus@bluegap.ch>

From: Markus Wanner <markus@bluegap.ch>
To: Bruce Momjian <bruce@momjian.us>
Cc: Robert Haas <robertmhaas@gmail.com>, Alvaro Herrera <alvherre@commandprompt.com>, PostgreSQL-development Hackers <pgsql-hackers@postgresql.org>
Date: 2010-08-09T18:13:05Z
Lists: pgsql-hackers
Hi,

On 08/09/2010 06:10 PM, Bruce Momjian wrote:
> My point is that you can treat malloc the same as "add shared memory",
> to some extent, with the same limiations.

Once one of the SLRU buffers is full, it cannot currently allocate from 
another SLRU buffer's unused memory area. That memory there is plain 
wasted at that moment. That's my point and the problem the allocator I 
posted tries to solve.

I fail to see how malloc could help here. malloc() only allocates 
process-local memory.

Regards

Markus Wanner