So I bought a 'portable' (2.5") 1T external hdd, reformatted it to ext4, exported it, and started copying ~60G from a mac over nfs. The first 6-7G stook 3-hours and the next 11 have taken ~1-hour. It seems a lot slower at copying large numbers of files vs. copying large (-ish) files. Anyway it won't be done and I'll have to resume another day. Thank fuck for cp -Rn.

How's it connected; USB2/3, e-sata, thunderboltsandlightning?

Sounds about right. 1GB of 1MB files takes far far longer than a single 1GB file.

Plus factor in the speed of your network. If you're on 100mbit ethernet then the absolute theoretical max you're going to get is 12.5 MB/s, but more like 10 MB/s.

GigE. It was hitting ~18MB/s on the bigger files which I figured maxed out USB2 (the hdd is USB3, but I'll need an add-in card for the pc). Most of the files during the slow part were <16 kb (web projects)

Yeah, the tiny files will take an age.

Recently got a USB 3 drive to replace yet another dead internal drive (thankfully managed a full backup before it went totally dead), it was mainly files larger than around 200 MB and the transfer speeds were as if it was an internal drive, very impressed.

Yeah USB 3 is amazingly fast.

I used to run a windows install from a USB2 hard drive. It was fine :C

I've got a USB 2 drive as a network share on the same pc as the portable one I just bought, it's fast enough, but I'm generally not trying to write crazy amounts of tiny files to it at one go.

Plugged in the new external drive to my home pc this morning and it wouldn't mount. I could hear an ominous clicking... Turns out the new-fangled USB 3 drives need more power than a USB 2 port provides (per mfg's web site faq), so I plugged it into a powered hub I happen to have for travel, and it works fine.

This morning I was unable to mount the portable drive's nfs share on my mac, so I nfs-mounted the mac source hdd on the ubuntu pc (where the portable is plugged in), and am running the copy from there, hitting >40 MB/s!