Re: Using Threads?

Adam Haberlach <adam@newsnipple.com>

From: Adam Haberlach <adam@newsnipple.com>
To: pgsql-hackers@postgresql.org
Date: 2000-12-04T23:17:00Z
Lists: pgsql-hackers
On Mon, Dec 04, 2000 at 02:28:10PM -0600, Bruce Guenter wrote:
> On Mon, Nov 27, 2000 at 11:42:24PM -0600, Junfeng Zhang wrote:
> > I am new to postgreSQL. When I read the documents, I find out the Postmaster
> > daemon actual spawns a new backend server process to serve a new client
> > request. Why not use threads instead? Is that just for a historical reason,
> > or some performance/implementation concern?
> 
> Once all the questions regarding "why not" have been answered, it would
> be good to also ask "why use threads?"  Do they simplify the code?  Do
> they offer significant performance or efficiency gains?  What do they
> give, other than being buzzword compliant?

	Typically (on a well-written OS, at least), the spawning of a thread
is much cheaper then the creation of a new process (via fork()).  Also,
since everything in a group of threads (I'll call 'em a team) shares the
same address space, there can be some memory overhead savings.

-- 
Adam Haberlach           |"California's the big burrito, Texas is the big
adam@newsnipple.com      | taco ... and following that theme, Florida is
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