Ramdisc + readyboost + SSD

I have a clever little script which can copy files from a staging area on boot to a RAM Drive and back the contents up on shutdown - only works on XP Pro though.

It provides, as people have said, decent performance increases for things like temporary storage, and the Firefox profile directory if you use that.

Disabling the paging file isn't going to make your PC become unstable, but it'll provide marginal performance benefits -- Windows will page out memory that's not been used in a while to disk to free it up, you'll probably have seen this if you've ever minimised a program for ages and then brought it back up, there's a bit of disk activity and lag.

Putting the page file on the SSD, as people have said, will wear it down a lot faster. But it is probably still the best place to put it - usually very small write packets, which are what SSDs are designed for.

Loading the OS to the RAM Drive will not work with Windows, I've seen people try, and not get any where. You can do it with Linux though, if you so desire (knoppix even gives you the command line option to do so).

I was actually considering doing what you originally planned, but the time to copy the game to the RAM Drive (installing it there would be a bad idea, if you had a power cut, it'd leave a mess of registry entries - DRM'd games especially) would negate any time you'd save from faster load times.
 
I disagree with a fair amount of that andrewdodd13. Copying things on startup and shutdown is easily done, but fails somewhat if the computer crashes.

Mattus has pointed out the flaw in your disabling paging file idea

Page file on ssd is firstly strongly advised against by everyone who makes them, and secondly just makes **** all sense compared with putting your operating system on it.

You can sort of do it with linux. I did so for a while. To do it cleanly features changing the initial ramdisk. You can force all of the operating system into ram if you wish, and if you're very careful you can save the changes you make. The most useful set up I had was in ram by default, /home on a physical drive. Upon reboot it discarded all changes to anywhere else. With an option to boot normally, to update os/change programs and so forth.
So yes, linux will do this, but it still requires care and thought as to how to set it up usefully. Boot times get worse though.

Copying 6gb or so to a ramdisk actually takes rather little time. Copying the data there from a normal install would make far more of a mess of things than installing it there and using imaging software. You want the registry to be pointed at your ramdisk, otherwise it wont run games from there.
 
Obviously ill need to research more but using a ramdisk is defintely something ive gotta look into.
Plus it gives me more stuff to mess around with ;)
Now would be a good time to win this euro lottery.
 
Mattus said:
So what happens when a program needs to allocate memory and there's no free RAM? It can't allocate memory from nowhere... the program will just crash.
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No, Windows will allocate an emergency page file.

Page file on ssd is firstly strongly advised against by everyone who makes them, and secondly just makes **** all sense compared with putting your operating system on it.
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I took that from a Microsoft post on the Engineering Windows 7 blog. See here.
 
unknownsock said:
Can't think of any off the top of my head, but your computer is always using the pagefile regardless of Ram.
Well im gonna read into using a ramdisc anyway.
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Pagefile is there for you to use your HDD space instead of RAM when there is not enough of it.

As long as you have enough RAM for all the things you run at the time, there is no pagefile needed at all. Also it's faster if you just use the RAM since its plenty faster than any kind of HDD.
 
andrewdodd13 said:
No, Windows will allocate an emergency page file.


I took that from a Microsoft post on the Engineering Windows 7 blog. See here.
Click to expand...

PhoenixUK said:
Pagefile is there for you to use your HDD space instead of RAM when there is not enough of it.

As long as you have enough RAM for all the things you run at the time, there is no pagefile needed at all. Also it's faster if you just use the RAM since its plenty faster than any kind of HDD.
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Both these statements are correct, there is no arguement in this issue, those are the facts.

Hawker
 
Microsoft do not make solid state drives. Therefore my statement that everyone who makes them advises against using them as ram stands, regardless of whether microsoft think its a good idea or not. I will leave this comment here if I can, as my feelings about microsoft are strong and not positive.

Care to suggest any reasoning that suggests os on hard drive with page file on ssd makes more sense than the other way around?

"Windows will allocate an emergency page file." seems sensible, and I would hope it would be the case. I've had solid edge crash on me because it has run out of memory however, which suggests this is not always the case.
 
JonJ678 said:
Microsoft do not make solid state drives. Therefore my statement that everyone who makes them advises against using them as ram stands, regardless of whether microsoft think its a good idea or not. I will leave this comment here if I can, as my feelings about microsoft are strong and not positive.

Care to suggest any reasoning that suggests os on hard drive with page file on ssd makes more sense than the other way around?

"Windows will allocate an emergency page file." seems sensible, and I would hope it would be the case. I've had solid edge crash on me because it has run out of memory however, which suggests this is not always the case.
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I didn't suggest putting the OS on an HDD. The thing is though, with the drastically reduced access times of an SSD there's nothing stopping you from putting both on the same SSD.

I believe Windows will only do this the first time it runs out of memory. So it will see "oh, there's 4GB in use, I'll allocate a 2GB swap file". If you then proceed to use the 2GB swap file as well (you'll have noticed by this point that performance will suck - you're dropping from 5GB/s to 200MB/s) then it won't allocate any more.
 
Except for the problems with lots of random writes interfering heavily with the speed of the drive, and the wear & tear associated with doing so. If Id used part of my ocz solid series for swap, it would have ground to a halt. See stuttering. My vertex deals a lot better, but still slows down appreciably if it's being treated as ram. Paging file on the data storage drive remains more sensible, but now I look it doesn't seem you were suggesting ssd + hdd above. I must have made this up, I'm sorry.

Shouldn't windows xp restrict a single program to 2gb though? Its possible solid edge threw up the wrong error, its not a very stable program. That was on 4gb ram, xp 32. However this is a good idea in general, I think I'm going to set up linux to do something similar. Have a 4gb file on my vertex (contradicting myself I know :) ) which has swapon executed against it when memory almost runs out, and swapoff when back to normal.

Cheers man. Learnt something today

edit: swap = virtual memory = paging file, near enough
 
hawker1986 said:
Pagefile can be safely disabled in any system with 4GB+ RAM
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I'm sorry but this is not correct. You cannot simply say you can safely disable the page file just because you have (x) amount of RAM. It ignores a system resource which the paging file has an impact on i.e. the system commit limit. If you do not take into account how much committed virtual memory your workload requires and it happens to be more than the amount of physical memory you have installed in the machine, you will start running into problems, which I have illustrated below.

The following screen shot is of an image of Process Explorer. Take note of the "Commit Charge (K)" box on the left hand side. The "Commit Charge Limit" represents the maximum amount of committed virtual memory processes can allocate at any one time and is the sum of roughly the amount of physical memory plus the size of the paging file(s). "Commit Charge Current" displays the amount of committed virtual memory processes which are currently active have allocated. Finally, "Commit Charge Peak" is the maximum amount of committed virtual memory processes have allocated since the system booted. Once the "Commit Charge Current" reaches the "Commit Charge Limit", in the best case scenario, you will start receiving "Your computer is low on memory" messages.

69ffe6cc.png


1b4ba97d.png


I guess the next question is, how to correctly size the paging file:

Mark Russinovich said:
How Big Should I Make the Paging File?

Perhaps one of the most commonly asked questions related to virtual memory is, how big should I make the paging file? There’s no end of ridiculous advice out on the web and in the newsstand magazines that cover Windows, and even Microsoft has published misleading recommendations. Almost all the suggestions are based on multiplying RAM size by some factor, with common values being 1.2, 1.5 and 2. Now that you understand the role that the paging file plays in defining a system’s commit limit and how processes contribute to the commit charge, you’re well positioned to see how useless such formulas truly are.

Since the commit limit sets an upper bound on how much private and pagefile-backed virtual memory can be allocated concurrently by running processes, the only way to reasonably size the paging file is to know the maximum total commit charge for the programs you like to have running at the same time. If the commit limit is smaller than that number, your programs won’t be able to allocate the virtual memory they want and will fail to run properly.

So how do you know how much commit charge your workloads require? You might have noticed in the screenshots that Windows tracks that number and Process Explorer shows it: Peak Commit Charge. To optimally size your paging file you should start all the applications you run at the same time, load typical data sets, and then note the commit charge peak (or look at this value after a period of time where you know maximum load was attained). Set the paging file minimum to be that value minus the amount of RAM in your system (if the value is negative, pick a minimum size to permit the kind of crash dump you are configured for). If you want to have some breathing room for potentially large commit demands, set the maximum to double that number.

Some feel having no paging file results in better performance, but in general, having a paging file means Windows can write pages on the modified list (which represent pages that aren’t being accessed actively but have not been saved to disk) out to the paging file, thus making that memory available for more useful purposes (processes or file cache). So while there may be some workloads that perform better with no paging file, in general having one will mean more usable memory being available to the system (never mind that Windows won’t be able to write kernel crash dumps without a paging file sized large enough to hold them).
Click to expand...

Pushing the Limits of Windows: Virtual Memory
 
Great post, Fire Wizard. Nicely proves what I was saying - that if you disable the pagefile and you run out of memory, your apps will start to crash.
 
if you manage to use 4gb of ram then Yes you need it but norm you can get away with not having an page file, if you keep on hitting 4gb offen you NEED more system ram in the first place or your system speed will Tank when it has to start using page file

if you use an page file and are getting to 3-3.5gb of ram windows will auto start pageing out stuff as it guess that you going to run out of ram soon
 
ramdisk can hold an os and boot from it if you do soft reboots only then the ram retains the information but it would be a lot of hassle, just get a nice hdd sorted first basically then worry about fancy stuff


dont know about ssd but you can forget about pagefiles if you always have enough physical ram, this is true of xp and win 7 because Ive often set zero pagefile to help with defrag, etc
Even MS wouldnt use the slowest ram possible when theres fast stuff going spare
Theres no emergency facility afaik, low memory would screw the programs up and with a slight possibility of requiring a reinstall of those programs


Even if you dont agree with the above, the short answer is buy enough ram and put the pagefile on a normal disk and it'll be fast as it can be


Readyboost is for the very smallest files I think because the seek time on a usb flash drive must be like 1ms compared to maybe ten times that for a hard drive . Not sure what the trade off point would be, maybe 300kb?

Thanks to cache algorhyms storing any small file used previously, both the drive and windows will operate these and the cpu and so on leaving very little benefit for readyboost which maybe stores the prefetch files?

Has anyone a good link or review of readyboost ?
 
I do appologise about my pagefile comment, I should have made it clearer just for the pedantic people on this forum, rather than keeping it simple for the OP who hadnt worked all this out himself. For the normal PC user, who doesnt do anything hardcore like run multiple VMs etc then in a PC with 4Gb+ RAM it can be safely turned off, because they will never use that much RAM for it to be a problem. Is that a better statement for you? But leexgx is completely correct, if your running stuff that uses that much RAM, likelyhood is you know enough to realise it and the function of pagefile, so youll get more RAM and that will solve the problem.

Hawker
 
As much as I agree with Firewizard something tells me that everyone who uses more than 3-3.5GB of RAM on daily basis has already got at least 6, 8 or 12GB of RAM on his system.
 
Phoenix has a point. It's difficult to fill 3gb with spyware however hard you try.

However there will be many people out there with 1 or 2gb of ram who routinely run out of memory, and they shouldn't turn it off.

I don't turn it off even with 8gb anymore, there was a large thread on here a while back where I argued for turning off the pagefile and lost. I might be able to dig it out

Here you go. Good read. Makes various pro pagefile points missed from this thread.
 
So feel free to tell me how my systems have been coping for a year without pagefile running without and problems or BSODs? And I run all sorts of programs from Games, office, VMs, photoshop, CAD etc etc etc.

Hawker
 
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