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View Full Version : [ubuntu] Nautilus slows as it goes



Clive McCarthy
February 17th, 2012, 04:42 PM
I was transferring 1,000 x 4.8MB images from a USB 2.0 connected CF memory card and found that the transfer rate slowed dramatically as the files were moved.

Initially Nautilus reported 15MB/sec but this slowed to just 5MB/sec as the task went on. The CF card is rated at 15MB/sec.

In fact it took three tries to move all the images because Nautilus exited without any message, twice. :confused:

What is going on? It is a very simple task but it is a little scary when I'm unloading my camera's images to have Nautilus crash.

gordintoronto
February 17th, 2012, 08:54 PM
Just opening a new file in a folder that contains 1,000 files, takes an astonishing length of time. If your drive contains bad sectors which have been remapped, that can make it worse.

Clive McCarthy
February 17th, 2012, 09:32 PM
Opening the CF card doesn't seem to be the problem. It is the file operations that have a problem. I was able to watch the transfer rate progressively collapse over a few tens of seconds. It is almost as if there was some kind of cache being filled which was being emptied at a much slower rate, though that doesn't quite make sense. I also suspect that the first attempts to move the files caused nautilus to crash because perhaps the transfer rate had become effectively zero!

gordintoronto
February 18th, 2012, 02:20 AM
When there are 900 pictures in the receiving folder, and number 901 comes along, everything grinds to a halt for a significant amount of time. During this period, the flash drive doesn't send anything, so the effective transfer rate falls off a cliff.

Clive McCarthy
February 18th, 2012, 03:00 AM
So what's the disease and what is the cure? Is the file system repeatedly traversing a growing linked-list of directory entries?

The destination drive has no bad sectors, so no remapping. It's formatted with ext4. There is lots of free disk space.