Readyboost a cheap ssd?

As I understand it:
Readyboost is a cache which typically resides on a usb or flash drive.

Any data on readyboost has a copy on the hdd.

It is limited to 4gb which looks like 8gb because data is compressed.

The advantage of flash is quick access times, but slow transfer times compared to a hdd.
Vista therefore puts only short blocks of data there which can be accessed faster than going to the hdd.

When looking to read hdd data, it will check readyboost to see if the data is there, so it can read it in faster.

Readyboost is not a substitute for memory.

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My theory is that a good 4gb readyboost can help system performance.

The bigger the cache, the more likely you are to find the data you want in it, therefore, get the max..4gb/8gb compressed.

Any accesses satisfied out of readyboost will not only be faster, but it will reduce the interference on the main hdd.

Vista will copy what it thinks is the most useful data to readyboost. This absolves me from trying to figure out what that is. Also, it might change over time. With 8gb to work with, I expect that most of the small blocks of the os will eventually get included in the cache, and perhaps some of my own data also. This will leave the hdd to do what it does best...long data transfers.

Using a large ssd for the os would be expensive today. It would help with the small data that readyboost handles, but would be worse for large data transfers. Also, some of the frequently accesed data might not be on the os hdd.

I have tried to find some recent benchmarks of readyboost devices, but not been satisfied with the results.

A raptor has an average seek of 4.6ms, and a average latency of 2.99ms, giving a positioning penalty of 8.10ms.
I think the equivalent on a flash usb drive is perhaps 0.5ms. The data transfer on a raptor might be 80mb/sec depending on where the data is. On a usb drive, this figure might be 5mb/sec. As I figure it, the break even point for response time is about 30k bytes.

For the best results, I would like to find the fastest 4gb readyboost device out there. ...at a decent price.
Any suggestions for this would be appreciated.

The fastest would be an i-ram device, assuming that it could be used as a readyboost device. It is a bit pricey, though, at over $200 on e-bay.

Next might be a small ssd. These are also pricey, and generally come in sizes over 4gb.

I don't know about compact flash cards. I have to look into them.

I think the most likely best device will be the simple usb thumb drive. When vista was being introduced, there were a number of tests which used random drives of dubious performance. Most of them are now obsolete. I can't seem to find any good reviews of 4gb thumb drives intended specifically for readyboost.
Can anyone supply some links here?

I will be going to max memory(8gb), and will use some of it for a virtual drive for temporaty internet cache.

I am not a fan of raid-0, but the thought just occurred to me that if I can get enough of the small random accesses off of the hdd, then the superior big block transfer of raid might actually be effective.



 

blueeyesm

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http://chris.pirillo.com/2006/05/24/vista-readyboost/

He used a thumb drive with Readyboost.


If only the developers at M$ would stop dreaming about data compression ... Its a waste of processing.
 
@blueeyesm:
Your link was almost two years old. I also have had trouble finding good current links.
The speed capability of the devices used is not known.
Also, I think it might take some time for vista to figure out your individual usage pattern to effectively cache the most appropriate data.
With modern multicore cpu's compression is a good idea. Costing a few microseconds from compression is worth many milliseconds in data transfer.

At the moment I still think the idea has merit with a good device.
 

cusimar9

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The USB Flash drive was (AFAIK) intended to be a substitute for RAM. Users who already have a computer and don't want to add more RAM themselves can just stick in a cheap USB stick and have a simple, quick speed advantage.

For anyone concerned about performance it would be far more beneficial to just fit 4GB of fast RAM. I'd be surprised if you saw any performance gains from a USB drive if you were already maxed out on RAM.