I have some problem with the performance of my WD EX2 Ultra. Its outgoing traffic (TX) seems max at 100 Mbps. I did several tests:
I can use Transmission on the NAS to download at more than 200 Mbps, so the switch and cable is well Gigabit.
I can copy from another NAS to my PC at more than 50 MB/s (both are of course connected using Gigabit ethernet).
From the NVIDIA Shield, speedtest shows 600 Mbps download, so the connection there is also Gigabit.
Both NAS, and my PC and the NVIDIA Shield are in the same LAN (2 different switches but all connected to the same mesh node).
When I copy file from the WD My cloud to either my PC or my Shield, the speed is max at 10 MB/s. Actually, occasionnally it starts at 30 MB/s then drop quickly to 10 MB/s then 8 MB/s (maybe some stats problem), sometimes between 5-6 MB/s (I really don’t expect that, nor have any explanation). About the Shield, I don’t have the exact number, but streaming BD at 112 Mbps, there is buffering every few minutes.
I try some settings, like forcing the network interface to 1000 Mbps instead of “Auto”, to no avail. Funnily, I can copy to the NAS steadily at 65 MB/s (so copy a 4 GB file to the NAS takes exactly one minute), but reading from the NAS is much much slower.
PS: the information in the “Device Activity” of the homepage is not reliable. Neither the chart (wrong scale, incorrect Tx). And I’m using the latest firmware 2.31.204.
PS2: I don’t use RAID, and there is not much free space in the HDDs (50 GB in the 2 TB, and 150 GB in the 3 TB, both are 10-year-old WD greens, not the original WD reds).
PS3: After some cleanup, I have now at least 10% free space in each disk, but it hasn’t changed anything.
There is something interesting. The RX packets are 2x more but the RX bytes are 5x less, it’s a 10:1 ratio. The packets/bytes ratio is low because it was night, I guess. That’s why I tried the second time, when there is active download/upload.
New RX packets: 211032 New RX bytes: 152021721 => 720 bytes
New TX packets: 226153 New TX bytes: 313679818 => 1388 bytes, almost max
Well, I’m sad as there is nothing that I can conclude
Some more random commands, I don’t know if they are useful…
root@WDEx2Ultra root # netstat -i
Kernel Interface table
Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
docke 1500 0 0 0 0 0 631 0 0 0 BMRU
egiga 1500 0 59531379 0 0 0 28986441 0 127 0 BMRU
egiga 1500 0 0 0 0 0 0 0 0 0 BMRU
egiga 1500 0 0 0 0 0 0 0 0 0 BMRU
lo 65536 0 67277 0 0 0 67277 0 0 0 LRU
root@WDEx2Ultra root # netstat -s
Ip:
58997553 total packets received
0 forwarded
3161 with unknown protocol
0 incoming packets discarded
58994383 incoming packets delivered
28286419 requests sent out
Icmp:
2009 ICMP messages received
323 input ICMP message failed.
ICMP input histogram:
destination unreachable: 1738
timeout in transit: 271
176 ICMP messages sent
0 ICMP messages failed
ICMP output histogram:
destination unreachable: 176
IcmpMsg:
InType3: 1738
InType11: 271
OutType3: 176
Tcp:
33049 active connections openings
6289 passive connection openings
1402 failed connection attempts
323 connection resets received
14 connections established
50003144 segments received
112979463 segments send out
307481 segments retransmited
2 bad segments received.
736 resets sent
Udp:
8939256 packets received
176 packets to unknown port received.
0 packet receive errors
20172707 packets sent
0 receive buffer errors
0 send buffer errors
UdpLite:
TcpExt:
29 resets received for embryonic SYN_RECV sockets
2 packets pruned from receive queue because of socket buffer overrun
13298 TCP sockets finished time wait in fast timer
17117 delayed acks sent
131 delayed acks further delayed because of locked socket
Quick ack mode was activated 4670 times
616290 packet headers predicted
28069045 acknowledgments not containing data payload received
21356062 predicted acknowledgments
46270 times recovered from packet loss by selective acknowledgements
Detected reordering 14 times using FACK
Detected reordering 55 times using SACK
Detected reordering 2 times using time stamp
5 congestion windows fully recovered without slow start
5 congestion windows partially recovered using Hoe heuristic
160 congestion windows recovered without slow start by DSACK
1279 congestion windows recovered without slow start after partial ack
TCPLostRetransmit: 3827
813 timeouts after SACK recovery
190 timeouts in loss state
265323 fast retransmits
2938 forward retransmits
11564 retransmits in slow start
6442 other TCP timeouts
TCPLossProbes: 38255
TCPLossProbeRecovery: 890
1245 SACK retransmits failed
2 packets collapsed in receive queue due to low socket buffer
4928 DSACKs sent for old packets
8 DSACKs sent for out of order packets
3321 DSACKs received
9 DSACKs for out of order packets received
222 connections reset due to unexpected data
71 connections reset due to early user close
1458 connections aborted due to timeout
TCPDSACKIgnoredOld: 193
TCPDSACKIgnoredNoUndo: 1118
TCPSpuriousRTOs: 1272
TCPSackShifted: 234123
TCPSackMerged: 183390
TCPSackShiftFallback: 153644
TCPDeferAcceptDrop: 2968
TCPRcvCoalesce: 20360
TCPOFOQueue: 437
TCPOFOMerge: 8
TCPChallengeACK: 53
TCPSYNChallenge: 51
TCPSpuriousRtxHostQueues: 229
IpExt:
InNoRoutes: 9
InMcastPkts: 54531
OutMcastPkts: 13632
InBcastPkts: 53629
OutBcastPkts: 1250
InOctets: -1
OutOctets: -1
InMcastOctets: 18565321
OutMcastOctets: 6539619
InBcastOctets: 6955362
OutBcastOctets: 144413
PS6: Then actually I’ve found something interesting. It is not the link speed (it helps to dismiss some unlikely hypothesis like 100 Mbps up/1000 Mbps down).
When I use scp (copy over ssh): from the NAS: 230 Mbps, to the NAS: 250 Mbps (the speed is steady, CPU around 60% when copy, less than 5% otherwise).
Then with FTP: both from and to the NAS at 130-160 Mbps, CPU around 45-65%.
This performance is much less than I expected (FTP performance should be the same as samba). Then I test again with samba.
Copy to NAS: between 300-600 Mbps
Copy from NAS: steady 650 Mbps (75 MB/s). But WTF? Last night when I tried it was less than 10 MB/s even after a reboot…
I did do several tests last night, when I was watching on my Shield, then went to my office to test with my PC. The performance was always poor. I’ll fix the topic title.
