virtual memory with 16gb ram installed
- Thread starter adbp1
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You can reduce it. There are arguments against deleting it completely though, So just reduce it to about 1-2gb.
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Microsoft recommend keeping the pagefile on your SSD
Having said that, with 16GB or more of RAM I doubt if it would really matter that much in practice, at least in normal use.
If I allow windows to manage my PF (I have 16GB RAM) then it allocates 16GB space to the page file, I manually set 1024MB minimum and 4096MB maximum limits and it doesn't allocate more than the minimum now.
The main reason being in the event of a blue screen it requires the pagefile.sys on the C: drive or you get limited diagnostics ability IIRC. That said it's a Photoshop PC not a business critical server, so what's the harm?
Oh and Mitzy - pipe down. Some of us have MS qualifications and actually know what we're talking about!
You're building a Photoshop machine, therefore:
- Have a decent size page file on your SSD. Personally, I'd go for 16GB. If you have a lot of high-res images open then your memory commitment will quickly exceed 16GB. Getting "out of memory" errors whilst working on unsaved work will result in you having a really really crappy day; so don't mess around setting a silly 1GB page file.
- Instruct Photoshop to store it scratch files on your SSD.
Saving space on your SSD is completely pointless.
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Soldato
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Always have a pagefile even if it means moving it to a secondary hard drive
Go read the documentation. You behave like a child.
Must. Stop. Laughing!
Windows doesn't really manage it in an intelligent way, it just makes it equal to your ram and allows it to go up to twice your ram, this might have been correct a long time ago when it could be assumed that people who spent loads on ram were doing stuff which could potentially require a lot more virtual memory on top of their ram.
With this no longer applying due to ram prices its probably best to force it to 512MB/1GB on the SSD, that way its much faster to access for any programs which like to "poke" the virtual memory (like photoshop) without it using too much valuable SSD space.
If you put it on a normal drive then you run the risk of the computer stalling while the drive is spun up to read something really tiny off it.
With this no longer applying due to ram prices its probably best to force it to 512MB/1GB on the SSD, that way its much faster to access for any programs which like to "poke" the virtual memory (like photoshop) without it using too much valuable SSD space.
If you put it on a normal drive then you run the risk of the computer stalling while the drive is spun up to read something really tiny off it.
This sentence makes no sense.
Virtual memory is ever present. In a virtualised memory operating system you cannot just "disable" it or overlook it. It is merely a way of mapping a virtual address space to either RAM or page file. It is a level of indirection that lets you swap (i.e. that's why sometimes they're called "swap files") a page of memory out from RAM to disk, and vice versa. That's all virtual memory is.
Just to be absolutely clear on this... virtual memory is NOT a "overflow" region. It is NOT something that is only called upon when RAM has run out.
Virtual memory and page files are two separate concepts, albeit inextricably linked.
Virtual memory is implemented right down in the MMU of the CPU hardware. It is called "protected mode", see: http://en.wikipedia.org/wiki/Protected_mode. Before this we had "real mode" which effectively meant the CPU was dealing with RAM memory addresses. Very low level and raw. Protected mode added a level of indirection, controllable by the OS, which meant the CPU would have to look up in its MMU first whether the virtual memory page was in RAM or whether it would need to raise a page fault interrupt to allow the OS to bring that page of memory in from the disk's page file.
Lastly, Windows like pretty much all mainstream OSes (Linux, OSX etc) set the CPU into protected mode as one of the very first operations when booting. Although it is possible (if the OS programmer wanted) to switch the CPU back to real mode (indeed, Windows 9x did just this); present day mainstream operating systems such as Windows never do this. And this is fundamentally why it is often said that is not actually possible to disable "virtual memory" on at least Windows.
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you are right, but unless you have studied computers the full explanation just ends up being a load of techno waffle, might as well be something read out on star trek for those people who just play games or do office work, "set the virtual memory to quantum leap levels, engage!" 
The end result with memory swapping is still much the same as it just being treated as extra "slow" memory, at least for normal users who don't have hundreds of extra processes running for server activities.
The reason I said about virtual memory being needed on top of the ram was because of how limited ram was a few years ago, you could have a complicated database program running which needed 3GB+ Ram, but your computer might only physically be able to take 1GB ram, thus the need for a lot of extra virtual memory, the same database program today would easily fit inside normal memory without the need for swapping any of it out or any other active processes into virtual memory.
The end result with memory swapping is still much the same as it just being treated as extra "slow" memory, at least for normal users who don't have hundreds of extra processes running for server activities.
The reason I said about virtual memory being needed on top of the ram was because of how limited ram was a few years ago, you could have a complicated database program running which needed 3GB+ Ram, but your computer might only physically be able to take 1GB ram, thus the need for a lot of extra virtual memory, the same database program today would easily fit inside normal memory without the need for swapping any of it out or any other active processes into virtual memory.
Stop saying it like that. It makes absolutely NO sense.
Virtual memory is of a static/fixed size. On 32-bit machines this was 4GB. On 64-bit machines this is 16 exbibytes (which is, er, a lot).
There is no "extra" virtual memory. Virtual memory is not an extra, it is not a second class citizen. It is a first class citizen when it comes to CPU and OS kernel design. You cannot mess with the size of virtual memory, other than by choosing between a 32 or 64-bit machine.
What you are referring to is the size of the page file. Or perhaps more accurately you're talking about the memory commitment in general.
Please stop thinking of the word "virtual" meaning "slow, cheap, second class, additional, reserve" memory. It is not. It is not anything of the sort. The word virtual is actually in reference to the fact that a full address space of either 32-bits or 64-bits or whatever has been ensured and can be fully represented to all processes, individually, running on that machine. It ensures that each process does not really need to worry about its memory concerns because the OS and CPU will take care of everything.
Virtual memory is of a static/fixed size. On 32-bit machines this was 4GB. On 64-bit machines this is 16 exbibytes (which is, er, a lot).
There is no "extra" virtual memory. Virtual memory is not an extra, it is not a second class citizen. It is a first class citizen when it comes to CPU and OS kernel design. You cannot mess with the size of virtual memory, other than by choosing between a 32 or 64-bit machine.
What you are referring to is the size of the page file. Or perhaps more accurately you're talking about the memory commitment in general.
Please stop thinking of the word "virtual" meaning "slow, cheap, second class, additional, reserve" memory. It is not. It is not anything of the sort. The word virtual is actually in reference to the fact that a full address space of either 32-bits or 64-bits or whatever has been ensured and can be fully represented to all processes, individually, running on that machine. It ensures that each process does not really need to worry about its memory concerns because the OS and CPU will take care of everything.
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