Why are transfers to my external firewire drive so slow?

January 29, 2008 7:14 PM

What kind of transfer speeds should I be expecting from my new external Firewire 800 drive?

I just hooked up my new WD MyBook Pro (the one with 3 different interfaces) to my Macbook Pro. After deleting all the junk that came installed on the drive, I started transferring over some of my stuff, starting with about 8gigs worth of backed-up DVDs (it was actually 2 DVD disc images). It took less than 5 minutes to transfer, but crapped out on me right before it finished giving me some cryptic error. I looked it up a bit and it seems to have something to do with the fact that the drive was still formatted in FAT32, which I would have changed anyway had I noticed that. So I reformatted the drive to HFS+ using Disc Utility, and started the transfers over again. This time it took about 20 minutes to transfer the same amount of data. After that was finished, I transfered about 3.5gigs worth of pictures and again this took longer than I would have expected, about 10 minutes.

Also, even after the transfers completed, the circular LED thing on the front of the enclosure is still rotating, which according to the manual means the drive is in use. Could this be related? Does anyone have any ideas as to what's going on?

posted by Venadium to computers & internet (10 answers total)

Some quick and dirty math says 8 gigs at 20 minutes is like 700+ mbps, which is pretty damn good. Youre theoretical limit is 800mbps. If you want more speed then you should have bought a computer with an esata interface and an esata external drive.
posted by damn dirty ape at 7:34 PM on January 29, 2008

Hmm, 8 gigs is 8192 megs over 1200 seconds is 6.8 megabytes/sec, or 54 megabits/sec. Sounds kind of slow, but maybe in the right ballpark. Just tried copying a 500 meg file to my USB2 external drive and I got about 17 megabytes/sec or 136 megabits/sec. (I'm running Linux but copying onto an NTFS target partition.)

The actual write speed to the drive is of course going to be a lot slower than the 800Mbps theoretical maximum because of various kinds of overhead. But even so, yours does seem a bit slow and I'm not sure what the explanation might be.

I'm not sure you can count the FAT32 result as a fair comparison, because it may have given up because of the 4G file size limit on the filesystem (maybe it only copied one of the two DVD images or something).
posted by dixie flatline at 7:51 PM on January 29, 2008

Are you running Leopard? It could be that Spotlight is indexing that drive during and after the files have finished transferring over, which might explain both the slowness and disk activity. Try adding the volume to Spotlight's privacy setting so it doesn't get indexed.
posted by phrayzee at 8:12 AM on January 30, 2008 [1 favorite]

What you may want to do as well is reformat the drive to HFS+. Most new drives I Have found come preformatted as FAT32 and definately slows things down IMHO.
posted by ShawnString at 8:48 AM on January 30, 2008

doh...should have finished you know....actually READING the rest of the question.

But I know I personally have seen at least 3 of those particular drives crap out. I would be very leery of any of those WD drives.
posted by ShawnString at 8:50 AM on January 30, 2008

I've found that by ejecting the drive, hitting the power button on the front of the enclosure, and then turning it back on and remounting it, I get the kinds of speeds I would expect. But eventually I'll go to copy something and it'll be slow again. I'm wondering if it has something to do with the drive putting itself to sleep after a period of inactivity. In any case I might just think about returning this thing and getting a LaCie or something.
posted by Venadium at 11:42 AM on January 30, 2008

I'd definitely second the recommendation about checking the Spotlight settings.

Sounds to me like something on your machine is actively working on something on the drive, and it doesn't start up until a few minutes after you plug it in/turn it on. This would explain the slowness and the activity light being on. Could be Spotlight or something else.

You could check what processes are active by using 'top' from the command line (don't know if there's a more Mac-like way to do this).
posted by dixie flatline at 11:54 AM on January 30, 2008

Just occurred to me that another thing to check would be Time Machine. I haven't used a Mac lately, but I think this thing is supposed to kick in almost automatically when you plug in a new external drive (although I suppose it would ask you at least one question about whether you wanted it). Maybe Time Machine is busy starting some backups.
posted by dixie flatline at 12:06 PM on January 30, 2008

Yeah, I don't trust those MyBook drives. I had one that worked great until two or three days after the warranty expired, then simply died. Fortunately I had most everything scattered around on various other systems as well, so I lost very little, but I've very leery of WD hardware.
posted by lhauser at 2:57 PM on January 30, 2008

I've just bought a Firewire 800 capable external disk and wanted to know the speed. So I've done a test to give you contextual information about what kind of performance to expect.

I've copied a directory with a few large movie files to my HFS+ formatted disk over the 9 pin Firewire 800 connection. I turned off spotlight for the external disk I wrote to and that disk isn't being backedup either.

1.47 billion bytes in 45 seconds equates to 31.2 Megabyte per second and 249 Megabit per second.

You can tell whether Time Machine is working by watching the icon next to the mounted disk in Finder. It will show a spinning vortex like icon.
posted by jouke at 11:24 AM on January 31, 2008