Dstat during transfer:

  0   0  99   0   0   1|   0     0 |1802B 4528B|   0     0 | 368   322 
  0   1  98   0   1   0|  52k  856k| 514B  224B|   0     0 | 419   513 
  0   1  44   0   2  53|  32k  104k|1472B 1191B|   0     0 |2638   433 
  0   0   0   0   2  98|  44k  128k| 767B  782B|   0     0 |4414   360 
  0   2   0   0   2  96|  88k  224k| 270k 8323k|   0     0 |4372   555 
  0   2   0   0   2  96|  36k  120k| 897B  797B|   0     0 |4652   338 
  1   2   0   0   4  93|  36k  104k| 311k 9554k|   0     0 |4206   494 
  0   2   0   0   2  96|  40k  128k| 378B  314B|   0     0 |4325   341 
  0   2   0   0   5  93| 120k  288k| 299k 9677k|   0     0 |4768   516 
  1   2   0   0   3  94| 448k  920k| 500B  440B|   0     0 |4553   551 
  0   2   0   0   3  95|  12k   96k| 317k 9375k|   0     0 |4283   324 
  0   0   0   0   2  98|  32k  152k| 617B  620B|   0     0 |4292   510 
  0   2   0   0   4  94|   0    24k| 287k 9717k|   0     0 |5048   306 
  1   2   0   0   2  95|   0    16k| 357B  314B|   0     0 |4610   411 
  0   2   0   2   3  93| 252k    0 | 354k 9445k|   0     0 |4203   343 
  0   1  66   0   0  33|1536k    0 | 472B  458B|   0     0 |1698   432 
  0   0  98   0   0   2|  52k  228k| 179k 6011k|   0     0 | 417   417 
  0   0  99   0   0   1|   0     0 |1331B 1058B|   0     0 | 386   404 







# increase TCP max buffer size
net.core.rmem_default = 256960
net.core.rmem_max = 16777216
net.core.wmem_default = 256960
net.core.wmem_max = 16777216

# Disable timestamps to avoid 12 byte overhead
net.ipv4.tcp_timestamps = 0

# increase Linux autotuning TCP buffer limits
# min, default, and max number of bytes to use
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216