$ dd if=/tmp/testfile of=/dev/null bs=1G
10+0 records in
10+0 records out
10737418240 bytes (11 GB, 10 GiB) copied, 2.07775 s, 5.2 GB/s$ fio --name=randwrite --ioengine=libaio --rw=randread --bs=4k --runtime=20 --filename=/tmp/testfile
randwrite: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=1
fio-2.16
Starting 1 process
Jobs: 1 (f=0): [f(1)] [100.0% done] [2397MB/0KB/0KB /s] [614K/0/0 iops] [eta 00m:00s]
randwrite: (groupid=0, jobs=1): err= 0: pid=5750: Mon May 4 04:19:09 2020
read : io=10240MB, bw=2105.3MB/s, iops=538947, runt= 4864msec
slat (usec): min=0, max=97, avg= 1.17, stdev= 0.94
clat (usec): min=0, max=62, avg= 0.16, stdev= 0.49
lat (usec): min=0, max=97, avg= 1.33, stdev= 1.04
clat percentiles (usec):
| 1.00th=[ 0], 5.00th=[ 0], 10.00th=[ 0], 20.00th=[ 0],
| 30.00th=[ 0], 40.00th=[ 0], 50.00th=[ 0], 60.00th=[ 0],
| 70.00th=[ 0], 80.00th=[ 0], 90.00th=[ 1], 95.00th=[ 1],
| 99.00th=[ 1], 99.50th=[ 1], 99.90th=[ 8], 99.95th=[ 10],
| 99.99th=[ 11]
lat (usec) : 2=99.88%, 4=0.01%, 10=0.05%, 20=0.06%, 50=0.01%
lat (usec) : 100=0.01%
cpu : usr=21.39%, sys=78.47%, ctx=51, majf=0, minf=8
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued : total=r=2621440/w=0/d=0, short=r=0/w=0/d=0, drop=r=0/w=0/d=0
latency : target=0, window=0, percentile=100.00%, depth=1
Run status group 0 (all jobs):
READ: io=10240MB, aggrb=2105.3MB/s, minb=2105.3MB/s, maxb=2105.3MB/s, mint=4864msec, maxt=4864msec
для переключения без обрыва сессий и/или одновременной работы нескольких каналов нужны iptables/nft, iproute2