1

This is the service which has the most Page faults on the services list in Win XP Professional. Also it is the most RAM consuming service i have running. Page faults have to do something with paging of memory addresses etc. The real process of doing that thing "the paging" is out of my scope but am really interested in learning more about it and its behaviour. What literally means coreserviceshell.exe has 481.510 page faults !?

Dumitru mitru
  • 59
  • 1
  • 4

2 Answers2

0

A page fault occurs when the process (a running program) attempts to access memory that has been swapped to disk. The operating system may shift memory to disk to allow programs to access more memory than the computer actually has, called virtual memory. A page fault is the operating system bringing that piece of memory (called a page) is loaded from the disk back into memory.

Is 481,510 page faults too many or too little? It depends on how long the process has been running. The real issue is not how many that have occurred it's the page fault rate, page faults per second in the Windows performance counters. If this is high, the system may be spending too much time loading or saving pages, called thrashing.

akton
  • 14,148
  • 3
  • 43
  • 47
  • hi, thank you for you answer. The process is on all the time. Now i have looked at the notebook which is using the very same program as the license is for 3-PCs, and that program is using coreserviceshell.exe on every computer. on notebook it's registered 19.xxx.xxx (19 million of page faults) at this time i'm writing this message. – Dumitru mitru Sep 01 '12 at 16:30
  • I find it quite "normal" considering that opera has about 5xx.xxx page faults, Firefox about 8xxx.xxx.xxx(millions) of page faults. I'm using them both in the moment and also are always my most opened programs. Could you make a conslusion out of it ? – Dumitru mitru Sep 01 '12 at 16:39
  • What number of page faults do are You receiving if you have any of these two programs opened ? – Dumitru mitru Sep 01 '12 at 17:46
0

A page fault happens whenever a process requests a memory page that belongs to its virtual space, but, at the moment of the request, is not available inside the main physical memory.

This is usually implies that the OS will load the page from disk to make it available to the process. Doing so, the OS may also choose to swap out some other page of the process, because not recently used, not frequently used or similar criteria.

A page is usually 4kb (4.096 bytes), so 481.510 page faults x 4.096 bytes = 1.972.264.960 bytes. This means a total of about 2 Gb of page faults (usually swapped to or from hard disk). If they happened in a very short time, it's time to buy another RAM module. If you measured them across a week or so, well, in this case it's not a problem.

Here you can find some more information about virtual and physical memory, paging and swapping.

Community
  • 1
  • 1
Avio
  • 2,700
  • 6
  • 30
  • 50
  • Hi! i doubt it's a RAM module problem of any kind. This process is on all the time. Now i have looked at the notebook which is using the very same program as the license is for 3-PCs, and that program is using coreserviceshell.exe on every computer. on notebook it's registered 19.xxx.xxx (19 million of page faults) at this time i'm writing this message. – Dumitru mitru Sep 01 '12 at 16:33
  • Now it is 20 million of page faults. I don't find it strange due to processes which are carrying out in nanoseconds and in that kind of measure so i don't now what to thik about it. ... – Dumitru mitru Sep 01 '12 at 16:35
  • What number of page faults do are You receiving if you have any of these two programs opened ? – Dumitru mitru Sep 01 '12 at 18:00