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jbecicka

10th Jun, 2013, 05:31 PM
Hi,
I have a network issue and I'd like to ask for help.
I use xbian alpha 5.

My π is connected using ethernet cable to wifi router. My laptop uses wifi (g).

If I scp files to raspberry, it is very slow (about 0.5MB/s) but if I scp files from raspberry to my laptop, the transfer speed is ok (1.5MB/s - probably limit of my wifi network).

I use external HDD, formatted using HFS+. And it is not source of the slowness:

Code:
> dd if=/dev/zero of=500mb.bin bs=1M count=500 oflag=direct
500+0 records in
500+0 records out
524288000 bytes (524 MB) copied, 26.4107 s, 19.9 MB/s

so the disk write speed is about 20MB/s. Any ideas why scp upload is 3 times slower than download?

Thanks.
Jan

rikardo1979

10th Jun, 2013, 05:36 PM
maybe speed of your SD card is affecting this

jbecicka

10th Jun, 2013, 05:56 PM
(10th Jun, 2013 05:36 PM)rikardo1979 Wrote: [ -> ]maybe speed of your SD card is affecting this
I'm not copying to SD card, but to USB attached disk.

Anyway SD card is also quite fast:
Code:
xbian@xbian ~ $ dd if=/dev/zero of=500mb.bin bs=1M count=500 oflag=direct
500+0 records in
500+0 records out
524288000 bytes (524 MB) copied, 57.592 s, 9.1 MB/s

t.becicka

10th Jun, 2013, 08:25 PM
I have very same trouble but I don't use wifi.

namtih

10th Jun, 2013, 09:46 PM
Check the CPU usage via "top" while transfering files. Perhaps it's the bottleneck due file encryption.

t.becicka

10th Jun, 2013, 10:56 PM
Top is high on wa. But the same situation via samba or ftp, eg. without encryption.

namtih

11th Jun, 2013, 12:04 AM
Is Samba and/or FTP faster or is it the same issue?

t.becicka

13th Jun, 2013, 08:37 PM
(11th Jun, 2013 12:04 AM)namtih Wrote: [ -> ]Is Samba and/or FTP faster or is it the same issue?

It is the same issue

mk01

15th Jun, 2013, 01:28 PM
is you usb hdd mounted with "sync" option?

(do a "mount" from terminal and check)

rikardo1979

15th Jun, 2013, 03:12 PM
what is the HW set up and details?

t.becicka

21st Jun, 2013, 05:34 PM
(15th Jun, 2013 01:28 PM)mk01 Wrote: [ -> ]is you usb hdd mounted with "sync" option?

(do a "mount" from terminal and check)

Yes, it's mounted with sync
(15th Jun, 2013 03:12 PM)rikardo1979 Wrote: [ -> ]what is the HW set up and details?

I don't know what You mean. It's pi model B with external USB3 HDD.

mk01

23rd Jun, 2013, 01:19 AM
(21st Jun, 2013 05:34 PM)t.becicka Wrote: [ -> ]Yes, it's mounted with sync

so that is you issue
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