Table of Contents

Usually I write memo in files in the storage under my Android phone.

Previously I use usb-tethering between Android phone and PC connection.

structure

mount sshfs + wifi direct

speed test between phone and PC

wifi direct

% iperf3 -c 192.168.49.1
Connecting to host 192.168.49.1, port 5201
[  4] local 192.168.49.80 port 42588 connected to 192.168.49.1 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec  6.64 MBytes  55.7 Mbits/sec    0    243 KBytes
[  4]   1.00-2.00   sec  5.90 MBytes  49.5 Mbits/sec    0    355 KBytes
[  4]   2.00-3.00   sec  5.53 MBytes  46.4 Mbits/sec    0    395 KBytes
[  4]   3.00-4.00   sec  5.53 MBytes  46.4 Mbits/sec    0    485 KBytes
[  4]   4.00-5.00   sec  3.04 MBytes  25.5 Mbits/sec    1    485 KBytes
[  4]   5.00-6.00   sec  5.41 MBytes  45.4 Mbits/sec    0    509 KBytes
[  4]   6.00-7.00   sec  5.72 MBytes  48.0 Mbits/sec    0    536 KBytes
[  4]   7.00-8.00   sec  5.97 MBytes  50.0 Mbits/sec    0    591 KBytes
[  4]   8.00-9.00   sec  6.23 MBytes  52.3 Mbits/sec    0    653 KBytes
[  4]   9.00-10.00  sec  6.25 MBytes  52.4 Mbits/sec    0    724 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Retr
[  4]   0.00-10.00  sec  56.2 MBytes  47.2 Mbits/sec    1             sender
[  4]   0.00-10.00  sec  52.6 MBytes  44.2 Mbits/sec                  receiver

wired

% iperf3 -c 192.168.42.129
Connecting to host 192.168.42.129, port 5201
[  4] local 192.168.42.143 port 38882 connected to 192.168.42.129 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec  18.9 MBytes   159 Mbits/sec    0    187 KBytes
[  4]   1.00-2.00   sec  19.2 MBytes   161 Mbits/sec    0    215 KBytes
[  4]   2.00-3.00   sec  19.3 MBytes   162 Mbits/sec    0    245 KBytes
[  4]   3.00-4.00   sec  19.1 MBytes   160 Mbits/sec    0    245 KBytes
[  4]   4.00-5.00   sec  19.3 MBytes   162 Mbits/sec    0    266 KBytes
[  4]   5.00-6.00   sec  19.3 MBytes   162 Mbits/sec    0    266 KBytes
[  4]   6.00-7.00   sec  19.2 MBytes   161 Mbits/sec    0    266 KBytes
[  4]   7.00-8.00   sec  19.4 MBytes   163 Mbits/sec    0    266 KBytes
[  4]   8.00-9.00   sec  19.0 MBytes   159 Mbits/sec    0    430 KBytes
[  4]   9.00-10.00  sec  19.2 MBytes   161 Mbits/sec    0    430 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Retr
[  4]   0.00-10.00  sec   192 MBytes   161 Mbits/sec    0             sender
[  4]   0.00-10.00  sec   191 MBytes   161 Mbits/sec                  receiver

So the wifi direct environment is 3~4 times slower than the wired one

sshfs brutual shutdown cause other problems

  • when you modify file which is mounted via sshfs, your editor may get stuck

  • shutdown gracefully when wifi is away

  • enable verbose log

behavior difference between wifi and usb

  • emacs goes hang over wifi-direct while it doesn’t over USB
  • using fuse in debugging mode shows over USB also failed, it seems because background may handle signal correctly for disconnection
  • fuse logs

tramp on termux

Some people say “tramp in emacs avoid this problem”

So I tried tramp after setting the following additionally.

(add-to-list 'tramp-remote-path "/data/data/com.termux/files/usr/bin" t)
(add-to-list 'tramp-remote-path "/data/data/com.termux/files/usr/bin/applets" t)

I feel this was so slow not reliable enough unfortunately.