high speed!

I've been very disappointed in my external USB laptop drive enclosure. Whenever I'd run my rdiff-backup or just a regular rsync backup (with --progress, because speed is what I'm nuts about) I'd get pissed off because the speed would only stay at arund 1-1.2MB per second.

Today though, I hit 5-5.5MB per second. I figure it was because I read some random advice (I think on the Philippine Linux users group mailing list) about plugging both USB jacks into the laptop because sometimes the power coming down one cable isn't enough (or the cable is substandard).

I'm a Psych major, so I never actually took any courses on electricity or electrical engineering (the computer science and computer engineering people do). I'm very glad though that, in fact, plugging in the second cable seems to have sped up the transfer rate. I may go buy a higher quality cable too as that is supposed to increase transfer rate too. For now though, ohhhh, 5+MBps is SOOoooo much better than 1+Mbps.

It's now fast enough that backups will be a joy, or only a minor nuisance, rather than the big production it used to be (I've got tens of gigabytes of data to transfer, it takes a while to rdiff-backup all of that, even if nothing's changed and all rdiff-backup has to do is read through the files to see if any bits have flipped).

[Update]
I don't think anymore it was the second cable (or the power issue). I think I probably got an kernel update that finally supports fast USB on this laptop. I experimented tonight, copying the data with both cables, and then with one cable. The speeds are the same. I'm still very glad to be getting 2.5-20MBps, all speeds are a lot faster than the 1.0-1.2MBps I'd get previously. But it's not the cable. That's too bad, since waiting for the kernel to get fixed for a particular laptop chipset is harder and less deterministic than just plugging in the other cable :-).

I'll keep the other cable plugged in though, still. I'm sure it'll help with stability, if the external drive gets enough power instead of sometimes getting too little.