Paging under Windows

[vladimir_golovtchiner]

Hello,

is it normal that under Windows 2003 in ST06 Transaktion Page\out biger as 0 and will be increased at the begining of backup?

But Page/in is each time 0. Have I some problems with memory configuration? I have no Performance problem now.

I have ever head that the Pagin mechanism is quet diferent as in Unix. Where such behavier meanse memory configuration problem.

Many thanks for your help

Vladimir

[Former Member]

For Windows operating system page-in activity is of concern as far as performance of the system is concerned, page-out activity is not performance-relevant for this OS.Windows operating systems can tolerate a page-in activity of up to 25% of the size of the physical memory per hour.

Reverse id true for UNIX OS. For UNIX-type systems, swap-in activity is not performance-relevant. UNIX-type operating systems can tolerate a swap-out activity of up to 20% of the

size of the physical memory per hour.

[Former Member]

The swap/paging activity on OS level per hour should not be higher than one-fourth the size of the physical RAM for page in activity on Windows OS, or one-fifth the size of the physical RAM for Page Out activity on UNIX OS. Otherwise, you will observe a decrease in SAP system performance caused by heavy CPU and I/O utilization.

regards,

dilip

[Former Member]

Hi Vladimir,

I guess the SAP Note 689818 "High Paging Rates during Backup" will clear us very well

in this regard which says that windows cant distinguish between normal IO to files on disk and IO to the paging area.

Hope it describes what we want.

Thank you,

Tilak

[Former Member]

With Windows, you will generally have more paging out than paging in.Here is a note that provides some background information: [Windows Server 2003 Family: High Paging Rates|https://service.sap.com/sap/support/notes/1009297]

Hope that is helpful.

J. Haynes