Large USB Flash Drive Performance

I just bought a 16 gig corsair to use as dedicated mp3 storage for my car stereo - and you’re right, it’s noticeably slower then my 4 gig corsair gt (durability and speed have always sold me as far as corsair goes)

while the speeds of pen drives are less than that of HDDs, why ppl say that pen drive ready boost is faster than hard disk cache?

On an unrelated note:
Your captcha is always orange(as far as i’ve seen. for about more than a month.) how is that spammers didn’t break that yet?

Also it’s very important to realize that some drives are better at reading/writing large files while others are better at reading/writing a lot of small files. Most of my files are code so they are small so I went with a drive that was better at small files (Super Talent 4GB).

The “32 GB Corsair Flash Voyager” link is broken.

I’m not in the hard drive performance matters camp. Hard drive performance is close to irrelevant. I already started some of our products from USB sticks that we on a USB 1.1 hub, so maximum throughput is 12 MBit/s and still, it takes only a couple of seconds to bring them up. If an application depends extremly on HD perfomance to oprate at good speed - it’s broken by design, like so often.

E.g. AdiumX, a chat client for MacOS X (supporting AIM, ICQ, Jabber, MSN, Yahoo, Google and many other) saves preferences frequently and this had a negative impact on performance if your prefs got very big. Now you can buy a faster HD to minizie this effect. But what the coders did was instead saving prefs asynchronously in an extra thread in the background and even with the slowest HD, you won’t notice anymore that it saves at all.

Even big games can hardly load more texture data from HD than you have memory (RAM) or v-memory (video memory). And if you look at their mimimum memory requirements, you’ll see that this is not a lot. Even if you have more memory, they won’t load a lot more data than the minimum memory requirements. And if a slow HD means big loading time for games, the game is badly programmed. Instead of loading all at once e.g. it could load dynamically in the background, making the game start very soon and then keep loading while you are already playing. And it could cache more data. Between two levels, not all textures, modells, sounds and so on change. Instead of reloading everything for every level, it should better keep already loaded material in memory.

Saying you need a faster HD for a faster app is like programming an app with horrible performance and relying on a faster CPU to one day fix that. That’s not the way to go. There are so little operations where throughput really matters. E.g. if you copy a 4 GB video file from driva A to drive B, that is a case where throughput really matters. However, if you access 10,000 small files (each just a couple of KB), throughput will be almost irrelevant compared to seek time. And here even good HDs only offer about 12 ms, while flash offers seek times in the ns range (milliseconds compared to nanoseconds), as they are usually below 1 ms. Actually, even with only 1/3 of the throughput, in some cases flash memory wins because of the little seek time.

It also depends a lot on OS. On Windows apps typically come with one or a couple of very large resource files (containing tons of data put together in one place). This is because the files are lying around visibly to the user and it just looks cleaner to have little files lying around. Unless the file is very fragmented, throughput might be important here. However, on Mac OS X, apps come in bundles. A bundle is a directory, but doesn’t look like one to the user (without going over the context menu or using terminal, there is no way to look into that bundle, it just looks like a single file to the user). Inside the bundle, every piece of data is usually an own file. Some bundles consist of 30,000 files inside. The user won’t see the mess anyway. Here seek time can be the important factor, not throughput. And I like the Apple way a lot more. Why? Well, if you just have very little huge files, you need to make sure you can seek within these files at reasonable speed. Finding data, jumping to it and loading it will become your task. On Mac OS X these are individual files. Finding them and jumping to them and loading them is task of the OS (and Apple can speed it up by improving the file system or offering better ATA drivers, and so on). So as developer you will gain performance from other people’s work, while in the Windows case MS optizimations will buy you little, as they don’t know how you seek within your proprietary archive.

I do not understand how flash drives can suck when it comes to random access. I thought that this was part of their beauty. The fact that they are memories and not hard-disks, so they don’t have to wait for disks to spin and heads to move. Maybe someone can clarify this for me.

Thinking aloud…how about partitioning in a few blocks that aligns with the USB drives flash memories? Then RAID the “disks” for Raid5?

Do not underestimate the special write-characteristics of flash memory - they indeed wear out, it’s physically inevitable. With large SSDs it might not be a problem as long as there is a lot of free space left, so the controller can evenly distribute writes over the whole thing. But on fuller “disks” - especially with certain access patterns like write intensive databases - this may cause drop outs much earlier.
I recently learned that DB2e (IBMs database for embedded devices) is “flash-aware”, i. e. it does not just flush to disk in the regular “fire-and-forget” way, but tries to accumulate write units that resemble the flash structure and also distributes write accesses inside its data files.
For storage and carrying around stuff, flash pens are really great, however I would not trust them for everyday work.

“I’m starting to wonder why we don’t just take our entire computing environment, operating system and all, along with us and boot it up on whatever computer we happen to encounter in the wild”

In fact you can already buy USB sticks with Linux and various apps preinstalled ( - sorry in Danish, staring at 50€ for 2Gb up to ~85€ for the 8Gb model)

Google translated in case anyone is interested:

akilan Said:
“Your captcha is always orange(as far as i’ve seen. for about more than a month.) how is that spammers didn’t break that yet?”

It must be the computer your on, or a co-incidence. I’m on Coding Horror often here at the office, and i get a range of things from “apple” to “spammersNO”.

Or not… But I guess it just proves that some anti-spam utility is a lot better than nothing at all.

I have had Ubuntu Linux installed on a WD Passport that I do plug into use on whatever computer I am using. I had a flash drive I used this way, but performance wasn’t that great I had the passport, so why not? It works out pretty well for me.

@akilan, Jeff has briefly mentioned this is a previous post about CAPTCHA. Basically, it’s only used on this site. Go to the following article (CAPTCHA is Dead, Long Live CAPTCHA!), search for orange and you’ll be looking at the relevant paragraph:

— Your captcha is always orange(as far as i’ve seen. for about more than a month.) how is that spammers didn’t break that yet?
akilan on June 3, 2008 04:26 AM

"CAPTCHA defeating tools are tailored to very specific inputs; if there’s little to no monetary incentive, odds are nobody will bother to customize one for yours. My ridiculously simple “orange” comment form protection is ample evidence of that."


I think I’ll start carrying a slimmed down version of Linux or something on a USB drive. It gives me a reason to buy one if nothing else. Definitely use encryption on all semi-private data you put on a flash drive though, and preferably include an application to decrypt it, for a few OSes. I can see why people don’t bother to though. I wouldn’t be too worried about someone getting hold of my CV though, as mentioned above. Lots of people make their CV available on a website about themselves, and if the CV doesn’t contain the address, then the domain reigstration details sometimes does. The best way to prevent privacy problems is to not be overly private in my mind.

Bring on the phase change solid state disk could be 500 times faster than current drives.

“Well, yeah, and you can buy $2 wine that will get you just as drunk as the $50 kind, too.”

Wine prices may not be the best comparison in this case, as a study shows that perception of taste is influenced by knowledge of the price of the wine:


“On the other hand, when tasters did not know any price comparisons, they rated the $5 wine as better than any of the others sampled.”

The Corsair’s body is rubber. The plastic ones break. For me, longevity is at least as important as xfer speeds.

It is amusing consumers have been stuck with 10k rpm hard drives for so long and actually think they are fast. I bought a 15k rpm Seagate Cheetah hard drive years ago.

Grogs - I think the concern was that if the CV on the keychain had the owner’s address, then the finder of a lost keychain would know which house and car the keys went with.