Multiple SAP Data directories

[Former Member]

Is there any technical reason why there are 4 sapdata directories for SAP systems?

Why not just use a sapdataALL directory?

Cheers

[former_member376769 · Accepted solution]

Philip,

The reason why you have multiple sapdata directories is for performance issue. For a productive system, the more you spread your data on multiple volumes, the less you will have contentions. Also, you may want to isolate some tables on specific physical disks.

An other reason to have multiple sapdata is with SAN systems, in order to expand your capacity, it is better to create new volume groups than expanding the size of the existing volume groups.

Best regards.

Frank Markarian

SAP America

[markus_doehr2 · Accepted solution]

If you have multiple SAN systems connected and you want to distribute the data - yes. If you have only one SAN system then it makes no difference if the lseek() in the file is done on different directories.

Markus

[markus_doehr2]

I think the reason behind that is historical.

In the "early days" those directories were spread over separate disks. I have seen much more directories (up to 75), depending on the system size.

Markus

[Former Member]

Hi,

I agree with Markus, besides that filesystem size limits where certainly a reason to have multiple sapdata dirs in the past. We have now only a single /oracle/SID/sapdata1 in most systems and only add sapdata2, when we get more disks (and a new volume group is needed).

Sometimes it is a bit troublesome through installations, because i am always having trouble with the sapinst and his directory mapping. But creating sapdataX -> sapdata1 links always works as a workaround

Regards, Michael