Hi,

a) A single SAPDB devspace is limited to 128GB. You would need at least 6
devspaces. If you have smaller
disks you would configure more devspaces, but that should not be a problem.
Customers tend to have 40 or more devspaces. Limiting resources are those
I/O worker threads per devspace needed. These are at least the thread and a
semaphore per worker thread (normally two per devspace).

b) So for 750 GB you cannot use a maschine with 512 MByte RAM. Reason is
that SAPDB uses a converter.
That means for each 8KB Page in Release 7.3 5,5 Bytes main memory are needed
to map from the logical
page number to the physical disk position. To keep this converter in memory,
memory must be large enough.
 750GB < 100M Pages -> ca. 550 MB main memory used for converter only. This
memory is not availiable as data cache, which is responsible for the
performance. The needed size of the data cache depends on the amount of
data really accessed. If only a small part of the data is accessed
regularily, it can be smaller...

Therefore i recommend for such big databases (which always tend to grow
furtheron...) to use a 
64Bit UNIX machine (unfortunatly right we have no ia64 Linux port).

CU
jrg



> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
> Sent: Freitag, 12. April 2002 15:39
> To: [EMAIL PROTECTED]
> Subject: Experience on linux/sapdb with VLDB (750 GIG)?
> 
> 
> Hi,
> 
> we are planing to do an OS/DB migration of an 4.0B Retail system with
> Oracle 8.0.4./SunOS to linux/sapdb. Does anybody have 
> experience on sapdb
> and very large databases. Can sapdb still handle 750 GIG or 
> is it to large
> ?How about the resources needed to handle an sapdb with linux 
> of that size,
> any experiences ?
> 
> Thank you for your help
> 
> Dominik Sobolewski
> Gambit Consulting GmbH
> 
> _______________________________________________
> sapdb.general mailing list
> [EMAIL PROTECTED]
> http://listserv.sap.com/mailman/listinfo/sapdb.general
> 
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