
> 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.
> 
Wouldn't this be the interface for a tablespace i/o manager ?
A tablespace has the advatage of only needing a number of files
for thousands of small tables, and reduces the overhead of many 
open file handles. A tablespace is also needed before raw devices
can be efficiently exploited.

Andreas

Wed, 19 May 1999 14:16:55 +0200
ZEUGSWETTER Andreas IZ5 <Andreas.Zeugswetter@telecom.at>
Re: [HACKERS] sgmr* vs. md*
> 
> > 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.
> > 
> Wouldn't this be the interface for a tablespace i/o manager ?
> A tablespace has the advatage of only needing a number of files
> for thousands of small tables, and reduces the overhead of many 
> open file handles. A tablespace is also needed before raw devices
> can be efficiently exploited.

Good point.

-- 
  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, Pennsylvania 19026

Wed, 19 May 1999 12:31:27 -0400 (EDT)
Bruce Momjian <maillist@candle.pha.pa.us>
Re: [HACKERS] sgmr* vs. md*