SQL Server Performance Forum – Threads Archive
Pagefile size and location
I am installing a system with 4Gb Ram on Windows 2003 with SQL2000 I have the following disk configuration: Disk0: Raid1 34Gb partition with OS Disk1: Raid1 29 GB partition with Application software (SAP) and 4Gb swapfile5 Gb partition and 4 Gb Swapfile Disk2: Raid1 34 Gb partition with SQL log file Disk3: Raid5 410 Gb partition with SQL Database
The first question i have is: how does windows write to its pagefile, in Paralell (spread out the data over the x logfiles simultaniously to increase performance) or start at file 1 till its full and continue with the next? The next is: I can put all the pagefiles on a single disk (disk0 or disk1) is this a better option? this way i decrease the stress on or the OS or the Application (SAP)
With Windows 2000, I was monitoring 2 swapfiles in differents disk.
What I see is: Use 1rst swapfile until full and then use the second.
I don’t know how SAP stress server, if higth then is better to put swapfile in disk0.
Luis Martin …Thus mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true.
Bertrand Russell
Having a page file allows your computer’s operating system to pretend that you have more RAM than you actually do. The least recently used files in RAM can be "swapped out" to your hard disk until they are needed later so that new files can be "swapped in" to RAM. One of the tips in this website refers:
Assuming that SQL Server is located on a dedicated server, the location of the PAGEFILE.SYS is not critical. This is because SQL Server does not normally do any paging on its own. If you do notice that your SQL Server is paging regularly, then it needs to be tuned appropriately so that paging is virtually stopped. Generally, leave the PAGEFILE.SYS file on the same drive as the operating system. _________
Satya SKJ
Moderator
SQL-Server-Performance.Com
SAP and SQL are both on the same server but i convinced the client to buy 2 extra disk to use for paging in RAID0. Arjan
If I where you I use new disk to slip database and kip pagefile in SO.
Luis Martin …Thus mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true.
Bertrand Russell
Any chance of seperating SAP and SQL server on different machines? _________
Satya SKJ
Moderator
SQL-Server-Performance.Com
The server is sized (not by me) to be able to handle both SAP and DB so we can’t buy an new server now. Luis, you mean put the two extra disk with de DB-array and put the swapfiles on the OS disk? Arjan
Yes, what I means is: If you have the chance to create a filegroup in new disk array and move some index, or some tables (most used) you will get more performace, and live swap in OS disk. Luis Martin …Thus mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true.
Bertrand Russell
Have you collected any PERFMON stuff on this pagefile issue, if you do not have any issue then leave it as it is. _________
Satya SKJ
Moderator
SQL-Server-Performance.Com
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