We are running Oracle 10g on a Quad Dual Core Windows 2003 x64 Enterprise Server with 16GB of memory. I notice that the Oracle process is only using 4.6 GB of Physical RAM and 10GB of Virtual memory. Performance monitor is showing that the server has 8GB Physical Memory free. This seems like oracle isn't using the free memory very efficiently and swapping a lot out to disk, is this something that can be tuned to boost performance or is it dynamically performed by the Oracle process?
Thanks for your help, I'm new to Oracle having worked mainly with MS SQL so go easy on me,
> We are running Oracle 10g on a Quad Dual Core Windows 2003 x64 > Enterprise Server with 16GB of memory. I notice that the Oracle > process is only using 4.6 GB of Physical RAM and 10GB of Virtual > memory. Performance monitor is showing that the server has 8GB > Physical Memory free. This seems like oracle isn't using the free > memory very efficiently and swapping a lot out to disk, is this > something that can be tuned to boost performance or is it dynamically > performed by the Oracle process?
> Thanks for your help, I'm new to Oracle having worked mainly with MS > SQL so go easy on me,
> Regards,
> Stephen
What evidence do you have that anything is being swapped to disk?
Go to http://tahiti.oracle.com and search for initialization parameters that related to memory utilization. It is completely configurable. But don't change anything based upon only the information provided above. Bigger does not equal better. You may have just wasted money putting too much RAM in the server. -- Daniel A. Morgan University of Washington damor...@x.washington.edu (replace x with u to respond) Puget Sound Oracle Users Group www.psoug.org
> We are running Oracle 10g on a Quad Dual Core Windows 2003 x64 > Enterprise Server with 16GB of memory. I notice that the Oracle > process is only using 4.6 GB of Physical RAM and 10GB of Virtual > memory. Performance monitor is showing that the server has 8GB > Physical Memory free. This seems like oracle isn't using the free > memory very efficiently and swapping a lot out to disk, is this > something that can be tuned to boost performance or is it dynamically > performed by the Oracle process?
> Thanks for your help, I'm new to Oracle having worked mainly with MS > SQL so go easy on me,
> Regards,
> Stephen
If you run oracle on a unix platform of some kind you may have better luck.
If you have properly installed and configured 64 bit oracle on a 64 bit os this sounds unusual.
> We are running Oracle 10g on a Quad Dual Core Windows 2003 x64 > Enterprise Server with 16GB of memory. I notice that the Oracle > process is only using 4.6 GB of Physical RAM and 10GB of Virtual > memory. Performance monitor is showing that the server has 8GB > Physical Memory free. This seems like oracle isn't using the free > memory very efficiently and swapping a lot out to disk, is this > something that can be tuned to boost performance or is it dynamically > performed by the Oracle process?
> Thanks for your help, I'm new to Oracle having worked mainly with MS > SQL so go easy on me,
> Regards,
> Stephen
metalink 657456.992 seems to show your problem exactly. Says "What I did find though, is whomever setup the Windows server set it up as a File Server. I removed that option and now my Oracle process is using 6 gigs of memory (5 for SGA, 500 megs for PGA and then some over head) ...My Page File Usage% is now at 1%."
> We are running Oracle 10g on a Quad Dual Core Windows 2003 x64 > Enterprise Server with 16GB of memory. I notice that the Oracle > process is only using 4.6 GB of Physical RAM and 10GB of Virtual > memory. Performance monitor is showing that the server has 8GB > Physical Memory free. This seems like oracle isn't using the free > memory very efficiently and swapping a lot out to disk, is this > something that can be tuned to boost performance or is it dynamically > performed by the Oracle process?
> Thanks for your help, I'm new to Oracle having worked mainly with MS > SQL so go easy on me,
> Regards,
> Stephen
Have you enabled large page support on Windows and Oracle, which causes Windows to use 4MB memory page sizes rather than 4KB memory pages? If so, I suspect that Performance Monitor is showing incorrect information. I am running Oracle 10.2.0.2 on Windows 2003 x64, total page file size for all drives is configured at 3124MB, yet Task Manager reports that PF usage is 13.3GB. In my case, system performance is great, so I am not too concerned about the inconsistent numbers.
Have you verified that the page file is actually 10GB in size?
Charles Hooper IT Manager/Oracle DBA K&M Machine-Fabricating, Inc.
Charles Hooper wrote: > Have you enabled large page support on Windows and Oracle, which > causes Windows to use 4MB memory page sizes rather than 4KB memory > pages? If so, I suspect that Performance Monitor is showing incorrect > information. I am running Oracle 10.2.0.2 on Windows 2003 x64, total > page file size for all drives is configured at 3124MB, yet Task > Manager reports that PF usage is 13.3GB. In my case, system > performance is great, so I am not too concerned about the inconsistent > numbers. > Have you verified that the page file is actually 10GB in size?
I have read quite a few of your posts and I think that:
a) you know what you're talking about
and
b) you genuinely try to help people.
I hope that this info can help you and/or others.
For Windows, there is a nifty/cool/rad/awesome(for Yanks only) - (choose term which hasn't gone out of fashion, or better yet, the one which has come back into fashion!!)
Go to www.sysinternals.com and go for procexp (process explorer).exe - it gives more reliable results than the Windows performance monitor.
Inconsistent numbers should not happen. The site also has a number of other useful bits and bobs for anyone concerned with performance.
> > We are running Oracle 10g on a Quad Dual Core Windows 2003 x64 > > Enterprise Server with 16GB of memory. I notice that the Oracle > > process is only using 4.6 GB of Physical RAM and 10GB of Virtual > > memory. Performance monitor is showing that the server has 8GB > > Physical Memory free. This seems like oracle isn't using the free > > memory very efficiently and swapping a lot out to disk, is this > > something that can be tuned to boost performance or is it dynamically > > performed by the Oracle process?
> > Thanks for your help, I'm new to Oracle having worked mainly with MS > > SQL so go easy on me,
> > Regards,
> > Stephen
> Have you enabled large page support on Windows and Oracle, which > causes Windows to use 4MB memory page sizes rather than 4KB memory > pages? If so, I suspect that Performance Monitor is showing incorrect > information. I am running Oracle 10.2.0.2 on Windows 2003 x64, total > page file size for all drives is configured at 3124MB, yet Task > Manager reports that PF usage is 13.3GB. In my case, system > performance is great, so I am not too concerned about the inconsistent > numbers.
> Have you verified that the page file is actually 10GB in size?
> Charles Hooper > IT Manager/Oracle DBA > K&M Machine-Fabricating, Inc.
Apart from that useful bit of advice, be warned that 64-bit Oracle on 64-bit Windows 2003 that runs on AMD processors will experience a massive performance hit as memory starts paging maniacally once total memory consumption hits about 12.8GB. It's a known bug, there's a TAR out on it, it's allegedly fixed in 10.2.0.3 (not yet tested, however), and it only affects AMD processor platforms.
Might not have any relevance to the OP, but I thought I'd mention it just in case...
> Charles Hooper wrote: > > Have you enabled large page support on Windows and Oracle, which > > causes Windows to use 4MB memory page sizes rather than 4KB memory > > pages? If so, I suspect that Performance Monitor is showing incorrect > > information. I am running Oracle 10.2.0.2 on Windows 2003 x64, total > > page file size for all drives is configured at 3124MB, yet Task > > Manager reports that PF usage is 13.3GB. In my case, system > > performance is great, so I am not too concerned about the inconsistent > > numbers. > > Have you verified that the page file is actually 10GB in size?
> I have read quite a few of your posts and I think > that:
> a) you know what you're talking about
> and
> b) you genuinely try to help people.
> I hope that this info can help you and/or others.
> For Windows, there is a nifty/cool/rad/awesome(for Yanks > only) - (choose term which hasn't gone out of fashion, or > better yet, the one which has come back into fashion!!)
> Go towww.sysinternals.comand go for procexp (process > explorer).exe - it gives more reliable results than > the Windows performance monitor.
> Inconsistent numbers should not happen. The site also > has a number of other useful bits and bobs for anyone > concerned with performance.
> Paul...
Thanks for the suggestion - I have not experimented with that utility in quite a while.
Looking at the page file on the hard drive, it is currently at 3,199,488KB, with an upper limit hard coded at 4,092MB (4,190,208KB).
Comparing the numbers between Process Explorer (now a Microsoft product) and Task Manager on Windows 2003 x64 are very consistently inconsistent. 16,772,124KB - 3,798,000KB ------------- 12,974,124KB physical memory in use +14,254,748KB page file in use ------------- 27,228,872KB total memory usage
-or-
12,974,124KB physical memory in use + 3,199,488KB actual page file size ------------- 16,173,612KB total memory usage
I *suspect* that the problem has to do with the memory page size being 4096KB for applications using large page support, rather than the expected 4KB memory page size. There is probably a bit of code in Windows that does not yet recognize the change (this is a new feature for Windows), either that or Microsoft should patent the approach of jamming 14,254,748KB of data into a 3,199,488KB file. :-)
Charles Hooper IT Manager/Oracle DBA K&M Machine-Fabricating, Inc.
> On Aug 3, 9:09 pm, Charles Hooper <hooperc2...@yahoo.com> wrote: > > Have you enabled large page support on Windows and Oracle, which > > causes Windows to use 4MB memory page sizes rather than 4KB memory > > pages? If so, I suspect that Performance Monitor is showing incorrect > > information. I am running Oracle 10.2.0.2 on Windows 2003 x64, total > > page file size for all drives is configured at 3124MB, yet Task > > Manager reports that PF usage is 13.3GB. In my case, system > > performance is great, so I am not too concerned about the inconsistent > > numbers.
> > Have you verified that the page file is actually 10GB in size?
> > Charles Hooper > > IT Manager/Oracle DBA > > K&M Machine-Fabricating, Inc.
> Apart from that useful bit of advice, be warned that 64-bit Oracle on > 64-bit Windows 2003 that runs on AMD processors will experience a > massive performance hit as memory starts paging maniacally once total > memory consumption hits about 12.8GB. It's a known bug, there's a TAR > out on it, it's allegedly fixed in 10.2.0.3 (not yet tested, however), > and it only affects AMD processor platforms.
> Might not have any relevance to the OP, but I thought I'd mention it > just in case...
Thanks for posting the above. Interesting - I wonder if this issue/ inconsistency is a bit more widespread/different than Oracle believes. My servers have Intel processors. System performance is great, so I am not too concerned about the inconsistent numbers. But, if there is a real problem...
Charles Hooper IT Manager/Oracle DBA K&M Machine-Fabricating, Inc.
> On Aug 9, 6:14 pm, "Paul Linehan" <plinehan__A@T__yahoo__D.OT__COM> > wrote: > > I have read quite a few of your posts and I think > > that:
> > a) you know what you're talking about
> > and
> > b) you genuinely try to help people.
> > I hope that this info can help you and/or others.
> > ForWindows, there is a nifty/cool/rad/awesome(for Yanks > > only) - (choose term which hasn't gone out of fashion, or > > better yet, the one which has come back into fashion!!)
> > Go towww.sysinternals.comandgo for procexp (process > > explorer).exe - it gives more reliable results than > > theWindowsperformance monitor.
> > Inconsistent numbers should not happen. The site also > > has a number of other useful bits and bobs for anyone > > concerned with performance.
> > Paul...
> Thanks for the suggestion - I have not experimented with that utility > in quite a while.
> Looking at the page file on the hard drive, it is currently at > 3,199,488KB, with an upper limit hard coded at 4,092MB (4,190,208KB).
> Comparing the numbers between Process Explorer (now a Microsoft > product) and Task Manager onWindows2003x64 are very consistently > inconsistent. > 16,772,124KB > - 3,798,000KB > ------------- > 12,974,124KB physical memory in use > +14,254,748KB page file in use > ------------- > 27,228,872KB total memory usage
> -or-
> 12,974,124KB physical memory in use > + 3,199,488KB actual page file size > ------------- > 16,173,612KB total memory usage
> I *suspect* that the problem has to do with the memory page size being > 4096KB for applications using large page support, rather than the > expected 4KB memory page size. There is probably a bit of code inWindowsthat does not yet recognize the change (this is a new feature > forWindows), either that or Microsoft should patent the approach of > jamming 14,254,748KB of data into a 3,199,488KB file. :-)
> Charles Hooper > IT Manager/OracleDBA > K&M Machine-Fabricating, Inc.
A member of this forum suggested to me a different possible cause for the inconsistency of the page file usage numbers shown in the Task Manager and Process Explorer. So, I used Google to search Microsoft's site for additional clues.
It appears that on Windows XP and Windows 2003 Server that the "PF Usage" statistic (not present in previous versions of Windows) is NOT page file usage. Instead, it is total virtual memory usage for Windows and all applications, which includes both RAM and data stored in the page file (32 bit applications on 32 bit Windows have access to either a 2GB or 3GB virtual memory range). The "PF Usage" statistic is esentially the same as the "Commit Charge: Total" statistic, which is the size of the virtual memory in use by all processes.
http://www.microsoft.com/resources/documentation/windows/xp/all/prodd... Commit Charge (K): Memory allocated to programs and the operating system. Because of memory copied to the paging file, called virtual memory, the value listed under Peak may exceed the maximum physical memory. The value for Total is the same as that depicted in the Page File Usage History graph."
http://www.microsoft.com/technet/archive/winntas/maintain/monitor/03w... "Commit Charge Provides information on the total memory used by the operating system. Total lists all physical and virtual memory currently in use. Limit lists the total physical and virtual memory available. Peak lists the maximum memory used by the system since bootup."
http://www.microsoft.com/technet/prodtechnol/Windows2000Pro/reskit/pa... "To see how much virtual memory your Windows 2000 Professional-based computer uses, start all applications and use Task Manager to see the Peak Commit Charge value. This value appears in the Commit Charge box on the Performance tab. Commit charge is the number of pages reserved for virtual memory that are backed by the paging file. Peak committed memory is the highest amount of virtual memory (in bytes) that has been committed over this sample. To be committed, these bytes must either have a corresponding amount of storage available on disk or in main memory. Compare this value against the size of the paging file to determine whether the paging file is sized appropriately."
http://www.microsoft.com/technet/archive/ntwrkstn/reskit/03tools.mspx... Shows "Mem Usage" where later versions of Windows show "PF Usage". Windows Vista shows "Memory" in the same location. The "Page File" statistic in Vista, which is currently 1471MB (roughly 1,507,328KB) on my laptop, matches up very closely with the value 1,512,852KB reported by "Commit Charge Current" in Process Explorer.
Note that there is a bit of inconsistency in the above quotes, which are all from various Microsoft sources. From the above, using the numbers that I previously posted: 14,254,748KB (PF Usage, Commit charge total) -16,772,124KB (Physical memory total) + 3,798,000KB (Physical memory available) ------------- 1,280,624KB (Calculated page file size in use)
This seems to make a bit more sense, as the calculated page file in use falls below the hard coded maximum page file size of 4,190,208KB.
Thanks to Paul Linehan for suggesting the Process Explorer utility, Howard Rogers for providing a reference to a related Oracle bug, and Yong Huang for suggesting that there is possibly a different explanation for the inconsistency.
Charles Hooper IT Manager/Oracle DBA K&M Machine-Fabricating, Inc.
