maemo.org - Talk - Speed of USB file transfer

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- Nokia N810 (https://talk.maemo.org/forumdisplay.php?f=28)

- - Speed of USB file transfer (https://talk.maemo.org/showthread.php?t=28077)

Speed of USB file transfer

When I connect my N810 to my computer using the USB cable that came with it it appears as another drive. If I copy some files to it the performance is very slow - it takes a few minutes to copy 100MB, and all the while, the CPU is burning away at 100%.

Downloading files using the N810 off the internet also results in the CPU running very high. Does anyone have the same experience, or is this not normal?

Thanks!

Re: Speed of USB file transfer

Do you mean the cpu of the n810? if so run top in terminal and post what is using the cpu?

ps- I find using ssh much easier that having to plug wires in (you can use fireftp on firefox for an easy ssftp client)

Re: Speed of USB file transfer

This is not normal and sounds as if the memory card is very slow. Are you copying to the built-in memory card, or do you use an external one?
Maybe the card is corrupt and causes a lot of read-errors, resulting in slowness and high CPU usage because of constant retrying.

Re: Speed of USB file transfer

Thanks for your responses..

@pycage: Its to a new memory card which I put into the N810. I dont have a card reader to test it independently of the N810, but I do have another memory card that I could borrow and try to rule out the card.. I'll do that today and see if it makes any difference.

@xopher_mc: Yep I mean the CPU on the n810. I've done what you suggested, and this is what I've come up with:

When its not doing anything:

Code:

Mem: 124632K used, 2164K free, 0K shrd, 16696K buff, 37884K cached

Load average: 0.85 0.45 0.19

  PID USER     STATUS   VSZ  PPID %CPU %MEM COMMAND

  800 root     SW<    11436   351  6.0  9.0 Xomap

 1166 user     SW<    68408  1086  5.2 53.8 maemo-launcher

14859 root     RW      1960 14845  2.3  1.5 top

   82 root     SW<        0     6  0.3  0.0 OMAP McSPI/0

 1057 root     SW<        0     6  0.1  0.0 file-storage-ga

  846 user     SW<    95784   351  0.0 75.4 osso-media-serv

13057 user     SW     67660  1354  0.0 53.2 browserd

 1354 user     SW     40856     1  0.0 32.1 browserd

 1023 user     SW     35236     1  0.0 27.7 gnome-vfs-daemo

 1291 user     SW<    32104  1086  0.0 25.2 maemo-launcher

 1114 user     SW<    31436  1086  0.0 24.7 maemo-launcher

  953 systemui SW<    26236   351  0.0 20.6 systemui

When I'm copying a file from my laptop to the N810 via USB, to mmc2 (my memory card in the N810 - not the built in one)
I'm getting only 1.2MB/second, and the results of top are:

Code:

Mem: 124712K used, 2084K free, 0K shrd, 22572K buff, 32204K cached

Load average: 1.17 0.69 0.32

  PID USER     STATUS   VSZ  PPID %CPU %MEM COMMAND

 1057 root     SW<        0     6 30.6  0.0 file-storage-ga

 1166 user     SW<    68408  1086  8.5 53.8 maemo-launcher

 8680 root     SW<        0     6  7.2  0.0 mmcqd

  800 root     SW<    11436   351  6.5  9.0 Xomap

14924 root     RW      1960 14845  2.2  1.5 top

  119 root     SW<        0     6  0.7  0.0 kswapd0

14837 root     SW      6036   966  0.5  4.7 sshd

   82 root     SW<        0     6  0.5  0.0 OMAP McSPI/0

  289 root     SW<        0     6  0.5  0.0 kondemand/0

  408 root     SW<        0     6  0.3  0.0 cx3110x

  846 user     SW<    95784   351  0.0 75.4 osso-media-serv

13057 user     SW     67660  1354  0.0 53.2 browserd

 1354 user     SW     40856     1  0.0 32.1 browserd

 1023 user     SW     35236     1  0.0 27.7 gnome-vfs-daemo

 1291 user     SW<    32104  1086  0.0 25.2 maemo-launcher

 1114 user     SW<    31436  1086  0.0 24.7 maemo-launcher

So I can see its not maxing out the CPU.. I thought it was based on the load-applet which showed 100% (not sure why).. but still the 1.2MB/s speed is very annoying. Any ideas if the results of top indicate a problem?

Thanks!

Re: Speed of USB file transfer

Quote:

Originally Posted by rdurant (Post 277352)

Downloading files using the N810 off the internet also results in the CPU running very high. Does anyone have the same experience, or is this not normal?

Depends on protocol. For example if you download/copy via SSH you *will* max your CPU out. If you copy the same file with ftp, the transfer rate won't be considerably different, but will have only 20-25% CPU use.

As for USB, the speed of the card comes into play, and also take into account that the data is transferred twice - from the computer to the NIT (and USB is not too CPU friendly to boot, this is what you see in top), and from the NIT to the flash (and this one is not visible readily through top). Also, any running applications are not helping you either. If you really want to copy large amounts of data, I'd recommend taking the card out and writing to it directly. In my case that's a sustained 1.5MB/s versus 17MB/s difference.