can someone explain to me why ESXi 5.5, 6.0 have very very slow throughput within the ESXi system? even on the loopback interface, I had test this on multiple computer and it is about the same result. 3.81GB within the ESXi system?
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Server listening on TCP port 5001
TCP window size: 1.00 MByte
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[ 4] local 127.0.0.1 port 5001 connected with 127.0.0.1 port 50572
[ 4] 0.0-10.0 sec 4.44 GBytes 3.81 Gbits/sec
[ 5] local 127.0.0.1 port 5001 connected with 127.0.0.1 port 56499
[ 5] 0.0-10.0 sec 4.44 GBytes 3.81 Gbits/sec
[ 4] local 172.1.1.135 port 5001 connected with 172.1.1.135 port 37692
[ 4] 0.0-10.0 sec 4.44 GBytes 3.81 Gbits/sec
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below is the same test done on the VM sit in the same host as ESXi above, as you can see, it able to get more than 22.0 Gbits/sec within the VM
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Client connecting to 127.0.0.1, TCP port 5001
TCP window size: 1.00 MByte
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[ 3] local 127.0.0.1 port 32899 connected with 127.0.0.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 27.7 GBytes 23.8 Gbits/sec
real 0m10.353s
user 0m0.781s
sys 0m9.191s
root@napp-it-15b:/usr/local/bin# time ./iperf -c172.100.1.25 -w 1M
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Client connecting to 172.100.1.25, TCP port 5001
TCP window size: 1.00 MByte
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[ 3] local 172.100.1.25 port 45014 connected with 172.100.1.25 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 25.7 GBytes 22.0 Gbits/sec
real 0m10.493s
user 0m0.796s
sys 0m9.172s
did I missed something or it problems with ESXi slow network ?