Mitsu3000gt
02-19-2015, 10:50 AM
Does anyone know why my transfer speeds might always start high, and then slowly degrade to settle at some level way below where it starts?
For Example:
I have 160 MB/s read/write CF cards. I put them in a Sandisk Imagemate USB 3.0 reader that has been tested and reviewed to be able to max out the cards no problem. Transfers will start off at 160 MB/s (from card to computer), and it will stay maxed out for 10 sec or so, but then slowly degrades down to 70-80 MB/s over maybe 30ish seconds and stays locked there for the majority of the transfer.
It seems slightly better when I plug it into a USB 3.0 port right on my Mobo rather than on one of the case-front USB 3.0 ports, but nothing too significant.
I notice similar behavior when writing to my USB 3.0 LaCie external hard drive - it will start off around 120 MB/s, and then slowly degrade to 80MB/s or so.
Doesn't seem to matter if I am transferring hundreds of photos or a single large movie file, the same thing happens.
Is there a buffer somewhere in my computer that eventually fills and creates a bottleneck? That's the only thing I can think of why this sort of thing would start fast (at the advertised speeds I would expect) and then degrade to 50-60% of that number.
Also, on the writing side of things (computer to USB Flash Drive), it will do the same thing - start out super fast (my MoBo does have some sort of boost feature, perhaps that is part of it), and then eventually settles at a speed about half of what the USB drive is rated at.
I'm just trying to figure out if there is something going on with my computer, or if this is normal behavior. I don't remember dealing with such dependencies in the past, however my previous computer did not have USB 3.0 so I was happy when I saw 30 MB/s over USB 2.0 haha.
For Example:
I have 160 MB/s read/write CF cards. I put them in a Sandisk Imagemate USB 3.0 reader that has been tested and reviewed to be able to max out the cards no problem. Transfers will start off at 160 MB/s (from card to computer), and it will stay maxed out for 10 sec or so, but then slowly degrades down to 70-80 MB/s over maybe 30ish seconds and stays locked there for the majority of the transfer.
It seems slightly better when I plug it into a USB 3.0 port right on my Mobo rather than on one of the case-front USB 3.0 ports, but nothing too significant.
I notice similar behavior when writing to my USB 3.0 LaCie external hard drive - it will start off around 120 MB/s, and then slowly degrade to 80MB/s or so.
Doesn't seem to matter if I am transferring hundreds of photos or a single large movie file, the same thing happens.
Is there a buffer somewhere in my computer that eventually fills and creates a bottleneck? That's the only thing I can think of why this sort of thing would start fast (at the advertised speeds I would expect) and then degrade to 50-60% of that number.
Also, on the writing side of things (computer to USB Flash Drive), it will do the same thing - start out super fast (my MoBo does have some sort of boost feature, perhaps that is part of it), and then eventually settles at a speed about half of what the USB drive is rated at.
I'm just trying to figure out if there is something going on with my computer, or if this is normal behavior. I don't remember dealing with such dependencies in the past, however my previous computer did not have USB 3.0 so I was happy when I saw 30 MB/s over USB 2.0 haha.