This thread is for discussion of RAMdisks and RAMdrives (software and/or hardware devices). I used to be pretty cynical about this stuff. More gimmick than use. But with my recent purchase of a SSD for a netbook, and an inability to "move" temp files to a second HDD, I started looking into RAMdisks as a way to manage the write-thrashing issue. Here are my results, and also the discovery that a RAMdisk can even speed up browsing on a netbook that already has a SSD!
A RAMdisk is a virtual disk that exists in RAM memory rather than as physical media. A RAMdisk is typically set up in available system RAM. More here
A RAMdrive is like a RAMdisk other than it uses dedicated RAM on separate hardware rather than using an allocation of available system RAM. An example here
RAMdisks/drives can be fully volatile. When the PC is turned off, the power is lost, and the data is lost.
RAMdisks/drives can be battery backed. When the PC is turned off, the data is retained, so long as the battery has charge. Some devices are designed to draw a small about of memory from the PSU standby power so that the battery is always being charged.
RAMdisks/drives can also page-off the data to physical media, like HDD on shutdown. A software utility creates an image, saves it, before shutting off. It then reloads this image when the computer boots.
Why use a RAMdisk/drive?
Memory is much faster than HDD. Obviously. It also turns out to be a lot faster than flash memory (as used by SSDs). It means, with judicious use, you can get significant speedups over a HDD, even over a SSD. In fact, initial testing on my side, has shown that a RAMdisk can be up to 10x faster than a SSD, and 100x faster than a HDD in some situations. Your milage will vary.
There is another significant benefit of using a RAMdisk if you have a SSD. Write thrashing. No matter how big the SSD cache, or the cleverness of wear-leveling algorithmns, if you CAN reduce the number of (unnecessary) writes, you will improve the half-life of your SSD, and in fact will get significant speed ups due to the way SSDs work... requiring large block erase and write cycles.
Another benefit of a RAMdisk WITHOUT backup, is that when you power down the PC the data is gone. Forever. No need to run system utility cleanups to wipe temp or confidential data.
Only for desktops? Only for massive RAM workstations?
No. I currently got myself drawn into using a RAMdisk on my netbook. The netbook was upgraded to SSD and 2GB. I was a little worried about the heavy write-thrashing due to all the internet surfing (tens of thousands of gifs, jpgs and cookies each day), and the antivirus running in the background and scanning and logging tens of times per second.
I have a 256MB RAMdisk on my netbook. Tiny. But about the right size for a days work of use. Give what Windows Task Manager says about memory use, I could probably up this to 512MB on my 2GB machine without a loss of performance hitting the pagefile. I would certainly have it at 512MB if the netbook had 4GB. But there's Atom for you... memory limited on intel chipset.
Surely no speed gains compared to SSD!
I kid you not. The netbook was a lot snappier upgrading from HDD to SSD. But it is faster still with the RAMdisk.
OK, what are my options?
I have looked into free RAMdisk solutions. Over the last couple of days, i have used:
- Gavotte http://www.techsnack.net/gavotte-ram...irtual-hardisk
- Dataram http://memory.dataram.com/products-a...ftware/ramdisk
- Romex http://www.romexsoftware.com/
I found the gavotte first. It's a utility based directly off the MS code provided on their tech site
. What "mr. gavotte" did, was write an installer and management utility for it, rather than having to use registry hacks. How to install it? Check the link I provided above.
The gavotte ramdisk worked well. And it was fast.
I then tried the dataram product. The version is currently in "release candidate" edition, so is likely to be improved soon. I found the dataram product to be faster than the gavotte, especially with random 4K reads/writes. AND dataram had a PAE option, so that you can use more than 4GB even on 32bit OS. If, e.g., you system has 8GB of RAM (like my xeon workstation) but you use a 32bit OS, the RAMdisk can be placed in the "upper 4GB" which then doesnt affect available system RAM. NEAT. Only it bluescreen with me when I tried it. So the dataram product is faster, but not as stable as the gavotte?
I then found romex ramdisk. The website looks a bit cheap and cheesy, but the Free Edition of the software works very well and seems to be the fastest product of all three.
If you try more than one of the above RAMdisks, be SURE TO UNINSTALL/REMOVE the older version (and reboot) before installing the other product.
Where to install it?
On my netbook, I have installed 256MB (of 2GB) RAMdisk as a Z: drive. On my workstation, I have installed a 512MB (of 4GB) RAMdisk as a Z: drive. I would like to use PAE, but this is not available on gavotte, unstable on dataram, and a pay-for only option with romex. All programs have an option to automatically create a \TEMP folder. Select this, so that you can then use it for system TEMP files. See later how to do this.
What do you do with it?
You point all temp directories to it. e.g. internet temps, and windows temps. How?
IE > Tools > Internet options > Settings > General tab / Temporary internet files > Settings > Move folder > browse to z:
Rightclick My Computer > Properties > Environment Variables > then change as many user and system temps as you want to Z:
What kind of speedups can you expect?
With a SSD
With a RAMdisk
Yes, just sit back a minute and reflect on those figures. Now go to ccleaner and analyse... and look at those tens or hundreds of thousands of temp files. Wouldnt they fit better in the RAMdisk?
Put the pagefile in the RAMdisk?
General answer: No. Don't reduce your memory footprint to then put the pagefile in there. You are stealing with one hand to give to the other.
Specific answer: If you have COPIOUS amounts of unused memory, esp. if you are running 32bit OS with PAE, then yes, put the pagefile there. It is much faster to hit memory than a HDD or SSD. But keep the general answer in mind.
I think that many TPU members would benefit from setting up a small RAMdisk for their temp files. It will cost you 256-512MB of system memory, but I am sure you will "feel" the benefits.
Other software? Other setups? Your experience?
Please use the thread to discuss any other RAMdisk you might have sued or tested. Especially some of the commercial expensive ones. Link away. However, please add some feedback on why you would recommend an alternative over the suggestions above. Also, share your before-and-after results.
I am curious to see the performance results of some of our i7 friends running DDR3.