Running Win XP, turned off page file. Apparently it fills the blocks in the SSD thus turning off page file is good. Turned it off and everything appears normal. Am I on the right track? Thank you.

Running Win XP, turned off page file. Apparently it fills the blocks in the SSD thus turning off page file is good. Turned it off and everything appears normal. Am I on the right track? Thank you.

I disabled my page file once but had some issues, especially warnings in the Event Viewer I had not seen before. Reenabled and the warnings went away. Some programs won't run properly without a page file. If you Google turning off page file on SSD you'll see the community is in turmoil as to what is the proper thing to do. I'm leaving mine on. Best regards,Jim

It's a bad idea to completely disable your pagefile. Either reduce it from system managed to about 3GB if you have a small SSD, or move it to a secondary hard drive.

You only need a paging file so you won't get an OOM error if the RAM requirements of all loaded programs exceed your physical RAM. If you are running 32-bit Windows and have 4 GBy RAM you don't need a paging file because you can't address (use) more than 4GBy of memory anyway. With 64-bit Windows I would recommend using a paging file if you only have 4 GBy of physical RAM because the needs of Windows, FSX and add-ons can exceed 4 GBy. If you have 8 GBy of physical RAM, it is unlikely you will load programs requiring more than 8 GBy, so you don't really need a paging file. Cheers, - jahman.

This is such an old story.As Jahman said, it's only needed if your physical RAM is small. Since the times of XP, I've been turning off pagefile and never ran into any serious troubles. With XP I had 4GB, with 7 I had 8GB and I was never getting any problems.

If you are running 32-bit Windows and have 4 GBy RAM you don't need a paging file because you can't address (use) more than 4GBy of memory anyway.

If you load multiple programs in Windows that each address lots of memory - can the combinedmemory requirement not exceed the Windows address space? Quote: "The virtual address space for a process is the set of virtual memory addresses that it can use. The address space for each process is private and cannot be accessed by other processes unless it is shared.A virtual address does not represent the actual physical location of an object in memory; instead, the system maintains a page table for each process, which is an internal data structure used to translate virtual addresses into their corresponding physical addresses. Each time a thread references an address, the system translates the virtual address to a physical address.The virtual address space for 32-bit Windows is 4 gigabytes (GB) in size and divided into two partitions: one for use by the process and the other reserved for use by the system."

If you load multiple programs in Windows that each address lots of memory - can the combinedmemory requirement not exceed the Windows address space? Quote: "The virtual address space for a process is the set of virtual memory addresses that it can use. The address space for each process is private and cannot be accessed by other processes unless it is shared.A virtual address does not represent the actual physical location of an object in memory; instead, the system maintains a page table for each process, which is an internal data structure used to translate virtual addresses into their corresponding physical addresses. Each time a thread references an address, the system translates the virtual address to a physical address.The virtual address space for 32-bit Windows is 4 gigabytes (GB) in size and divided into two partitions: one for use by the process and the other reserved for use by the system."

The virtual address space is created by the operating system for each application and is mapped to a physical address space, part or all of which can be implemented in physical RAM. For a 32-bit operating system, the virtual address space, physical adress space and pysical RAM are all limited to 4 GBy each because 4Gig = 2^32 is the largest number than can be created in a binary numerical system using only 32 bits. So the rotund answer is no, it is not possible to simultaneously load apps exceeding 4 GBy (let's forget about Windows' own memory requirements for the time being) because all allocated virtual memory must be mapped into a physical address space and that physical address space is limited to 4 GBy for a 32-bit OS. Cheers, - jahman.

The way I read it, each process gets a 4GB address space to run in (minus OS reqts).. with it's own page table. This would allow multiple processes to be loaded, contending for physical space to run,and Windows allocating RAM as required, using the page file for stuff that does not fit into RAM.

The maximum memory 32-bit Windows NT/2000/XP/Vista/7 plus any loaded application can use is 4 GBy. If you have 4 GBy of RAM, then you're OK. If you have less than 4 GBy of RAM, you will need to instantiate a 4 GBy paging file (the maximum size allowed) so whatever physical RAM you actually have can be shared between the operating system and the loaded apps. Although in theory Windows could have been designed to allow a full 4 GBy virtual address space for each app, this is not the case. The reason is that while in ancient times apps were small and therefore memory swap times relatively fast, apps today are huge thus swap times too long to be practical. For example, swapping the 4 GBy of app A out to the page file to then load app B would reguire moving 8 GBy to/from the HDD, which at an average sustained speed of 80 MBy/Sec translates into 1 minute 43 seconds. Cheers, - jahman.

Interesting - I assumed that "in theory" Windows could load multiple big apps with a 4 GB (minus OS) address space each. No need to swap out the whole program though - the working set(s) could still be small.. Also, I currently have my paging file set to 4990 which is the "recommended size" as calculated bythe OS and larger than 4 GB.. confusing. Edited.. found in a Windows article: http://members.shaw.....htm#Additional

On any computer system, as load (number of users, amount of work being done) increases, performance (how long it takes to do each task) will decrease, but in a non linear fashion. Any increase in load (demand) beyond a certain point will result in a dramatic decrease in performance. This means that some resource is in critically short supply and has become a bottleneck.

At some point, the resource in critical short supply can not be increased. This means an architectural limit has been reached. Some commonly reported architectural limits in 32 bit Windows include:

1. 2 GB of shared virtual address space for the system

2. 2 GB of private virtual address space per process

3. 660 MB System PTE storage

4. 470 MB paged pool storage

5. 256 MB non-paged pool storage

6. 1 GB System cache

7. 16,000 GB pagefile size

RAM is a limited resource, whereas virtual memory is, to a large extent, unlimited in that there can be a large number of processes each with its own 4 GB virtual address space, of which 2 GB is private to the process (32 bit Windows). When the memory in use (that is, has been referenced) by all the existing processes exceeds the amount of RAM available, the operating system will move pages (4 KB pieces) of one or more virtual address spaces to the computer’s hard disk, thus freeing some RAM for other uses. In Windows systems, these “paged out” pages are stored in one or more files with the name pagefile.sys. There can be one such file in each disk partition.

No Bert, as jahman said, in a 32b OS, The VAS limit is 4GB. That's the total system VAS, with 2GB for the OS and 2GB for applications (all of them). For a single application the limit is 2GB too, so one application could theoreticaly take up the whole VAS.That can be modified with the userva & LAA tweaks to allow apps to get more VAS at the expense on the kernel's one as you surely knowWhat you describe is multiple LAA 32b applications in a 64b OS, where each one of those could use up to 4GB of VAS But in a 32b OS, you should allways have a paging file, even if you have 4GB of RAM, because some of it is reserved for device mapping and is not usable by the OS and apps, so there's still a chance of a page fault

Fascinating... in that case the MS article is incorrect...

ouch! EDIT: I stand corrected, thanks for that Bert

Edited August 3, 201114 yr by dazz

Well, yes and no. For example, under Win XP-32, the page file size is limited to a maximum of 4 GBy, thus the combined VAS of all loaded apps is also limitd to 4 GBy. (This is factual information, as the PC I use to post on AVSIM runs Win XP, and prior to my first post I tried to increase the size of my page file beyond 4 GBy and it didn't work.) Evidently as the OS matures Microsoft has relaxed some of the constraints built into its version of memory virtualization, of which I was unaware, so thanks for the heads-up un the article. Cheers, - jahman.

Personally I would not turn turn-off my page file regardless of SSD or HDD. My reason being a simple one of ignorance that commits me to the following of Dr. Mark Russinovich http://blogs.technet.com/b/markrussinovich/archive/2008/11/17/3155406.aspx At the end of the day Mark says eliminating the page file causes page faults that eat up any perceived performance benefit. There are programs that will not operate correctly without a page file. I have read much on the implication of writes to the SSD and I have drawn my own conclusion that it would take more years than I care to worry about to degrade its performance. In my own personal experience and as an fyi, I have found that setting the page file to system managed, affords a snappier response while internet browsing and using other programs such as Office. Can’t measure it, can’t prove it (nor do I care to), could be in my head, but I changed mine from 3072MB to system managed where it will remain for eternity consuming 8175MB of my 600GB HDD.