Thread: sgmr* vs. md*

I just changed the call from mdunlink to smgrunlink, but this brings up
a good point.

smgr is a generic i/o interface layer that allows multiple storage
managers.  Currently, we always use DEFAULT_SMGR as a parameter to smgr*
functions, causing calls to the md* routines.  Is there any value in
just removing the smgr layer completely.  It was originally for a CD
jutebox i/o layer in addition to our current disk i/o layer.

--  Bruce Momjian                        |  http://www.op.net/~candle maillist@candle.pha.pa.us            |  (610)
853-3000+  If your life is a hard drive,     |  830 Blythe Avenue +  Christ can be your backup.        |  Drexel Hill,
Pennsylvania19026
 

On Sun, 16 May 1999, Bruce Momjian wrote:
> I just changed the call from mdunlink to smgrunlink, but this brings up
> a good point.

Thanks, I should have noticed that myself...

> smgr is a generic i/o interface layer that allows multiple storage
> managers.  Currently, we always use DEFAULT_SMGR as a parameter to smgr*
> functions, causing calls to the md* routines.  Is there any value in
> just removing the smgr layer completely.  It was originally for a CD
> jutebox i/o layer in addition to our current disk i/o layer.

I think that extra layer is a very good idea.  Some new kind of storage
might come along that someone wants to use, and md.c wouldn't do the right
thing.

Since it's such a thin layer, performance doesn't really suffer.  Doesn't
hurt to keep it...

Ole Gjerde