Going slow?

January 27, 2007 2:35 PM

Is there a simple utility that tests data writing speeds? I have a new external device which purports to be USB 2.0 (as is my Win XP computer, I think), but just seems... slow. For example, 3.5GB just took 59 minutes to copy over from my HD to the external HD. How can I speed things up?
posted by jonathanbell to computers & internet (14 comments total)

That's USB 1 transfer speeds, you're probably not connected to a USB 1 port on your computer.
posted by onalark at 2:56 PM on January 27, 2007

If you want to speed things up, you want to connect your hard drive to a USB 2.0 port. Try connecting to other ports on your computer, and if you don't get a speedup with any of them, you might need to get a USB 2.0 expansion card.
posted by onalark at 2:57 PM on January 27, 2007

An external disk, or a USB stick, can either be optimized to be fastly removed, or have its writing cache on, in which case transporting data goes much faster.

Look under its 'properties'.
posted by ijsbrand at 3:16 PM on January 27, 2007

If it's a USB2 device, XP will normally whinge if you've plugged it into a USB1 port (even if that's all you have).

When you say '3.59Gb', was it one big file, or zillions of little files? This can make a huge difference, and testing on lots of little files isn't really going to show you the peak throughput.

As to the main question, I don't know of any particular testing app. I'd use a large file and a stopwatch.
posted by pompomtom at 3:21 PM on January 27, 2007

Was it a few large files or several smaller?

A shit-load of small files (like pictures) take a lot longer.
posted by Mick at 3:29 PM on January 27, 2007

Thanks for all the advice so far. It was about 9,000 smallish files. All my USB ports are definitely USB 2.0, according to the computer manual, as is the device itself (a Western Digital 'My Book', 500GB). No murmuring from XP about connection speed being slow or anything and in total I'm using 5 of 8 available USB ports built into a Dell Dimension 8300. Also, I'm copying the files using a Syncback SE Backup profile - perhaps that's slowing it down?
posted by jonathanbell at 3:41 PM on January 27, 2007

I was wrong, everybody else who posted about many small files are right. You could test for USB transfer rates by moving one large file (like a DVD or a CD image). This is pretty much all the test programs do.
posted by onalark at 4:30 PM on January 27, 2007

3.5GB shouldn't take 59 minutes, not even for 9 minutes.

However, you are using a backup utility, which probably verifies each copy. I bet if you use the windows explorer to copy it, it will go much faster.

Also, are you using the front ports? Those are normally USB1.1.
posted by mphuie at 5:48 PM on January 27, 2007

Oops, meant to say "not even for 9000 files".
posted by mphuie at 5:49 PM on January 27, 2007

I would use 'robocopy' (google it... its free from Microsoft) to copy the files to the USB drive.. that will do it the fastest way possible.

BTW.. you should be seeing around a one gig of data transfered every 1.5 minutes..
posted by cowmix at 5:52 PM on January 27, 2007

Note that there are two different speeds for USB 2.0, and they are quite different. Specifically, Hi speed (480 Mb/s) and Full speed (12 Mb/s). I haven't done the math, and I don't know the specs for 1.0/1.1, but there seems to be quite the range of speeds represented by 'USB 2.0'.
posted by philomathoholic at 12:36 AM on January 28, 2007

There is a lot of confusion about what the term USB 2.0 means. Many people think that it means that the device supports hi-speed (480Mb/s). That is not necessarily the case. Even a mouse operating at 1.5 MB/s can be designed to be compliant with the USB 2.0 specification. The USB 2.0 specification covers all devices, whether they operate at 1.5 Mb/s, 12 Mb/s or 480 Mb/s.

The proper designation for a 480 Mb/s device is to label it Hi-Speed USB as explained in this document at the USB Implementer's Forum. You need to look at the packaging to see if it has the Hi-Speed logo, regardless of what it says about USB 2.0. Only if it has the Hi-Speed logo can you be sure that the device supports the 480 Mb/s rate. Alternatively, the packaging may explicitly state in text that it supports the 480 Mb/s transfer rate. Unfortunately, some manufacturers use the term USB 2.0 when they really should say Hi-Speed so that there is ambiguity whenever you see this term.
posted by JackFlash at 1:45 AM on January 28, 2007

According to the box it is a 'high-speed USB 2.0' device, but even after a couple of re-boots data speed hasn't improved. I'll try swapping around the USB ports and see if that makes any difference.
posted by jonathanbell at 2:08 AM on January 28, 2007

Optimizing for quick removal, as is generally the default with removable devices in XP I think, severely pessimises the performance of copying many small files to a device -- instead of letting the system cache all the updates and perform writes out-of-order in nice big localized chunks, it flushes cache after each file, updates the MBR, waits for it all to complete, and then moves on to the next one.

I had this with my iPod Nano, - copying Rockbox to it involves a lot of small files, and I got about 20k/s out of it because it was waiting on each write. When I Optimized for Performance, speed increased about 100-fold.
posted by Freaky at 2:55 AM on January 28, 2007