Purpose of DBCC Commands

Please tell me what is the purpose of these DBCC Commands?
DBCC memospy
DBCC memobjlist
DBCC memorymap
DBCC DROPCLEANBUFFERS
DBCC FREEPROCCACHE
Can these commands be used to free the RAM which is occupied by SQL Server
Regards
Farhan Iqbal
While some of these are listed in BooksOnLine you can find some information
here:
http://www.sql-server-performance.co...ented_dbcc.asp
Undocumented DBCC commands
Andrew J. Kelly SQL MVP
"Farhan Iqbal" <mr_farhaniqbal@.hotmail.com> wrote in message
news:uVvBMKpwFHA.2880@.TK2MSFTNGP10.phx.gbl...
> Please tell me what is the purpose of these DBCC Commands?
>
> DBCC memospy
> DBCC memobjlist
> DBCC memorymap
> DBCC DROPCLEANBUFFERS
> DBCC FREEPROCCACHE
>
> Can these commands be used to free the RAM which is occupied by SQL Server
> --
> Regards
> Farhan Iqbal
>
|||Farhan Iqbal wrote:
> Please tell me what is the purpose of these DBCC Commands?
>
> DBCC memospy
> DBCC memobjlist
> DBCC memorymap
> DBCC DROPCLEANBUFFERS
> DBCC FREEPROCCACHE
>
> Can these commands be used to free the RAM which is occupied by SQL
> Server
If you are finding that SQL Server is consuming too much memory and that
memory is better utilized by other services running on the server or for
the server OS itself, you should consider setting an upper memory limit
for SQL Server. SQL Server uses available memory as it reads pages of
data and does not, under normal circumstances, release this memory back
to the OS. That is done by design. Operations, like unoptimized queries
that read too many pages, can cause the data in the buffer cache to
cycle in and out, which further hinders performance because the pages
that would most likely be able to reused tend to get pushed out.
David Gugick
Quest Software
www.imceda.com
www.quest.com