HiI have recently purchased a ready Nas duo v2 ( 2 x 3tb Seagate barracuda drives - flexraid 0)Im seeing horrific read performance of around 1.5 MB/s where as write speed is around 4.5 MB/sReadyNas Duo V2 is connected to Sagemcom router (sky - fast Ethernet ports only) by what I presume is a cat5 cable included within the ready nas. I am then connecting wirelessly from mylaptop. ( 300MB/s wireless network adapter)Im totally stuck as to why read speed is 3 x slower than write speed, does anyone have any ideas where to look? ( there's not issue with the speed of the disks in my laptop as its using 2 SSD Drives (RAID 0) )Any suggestions / ideas at all welcomeThanks

-your wireless routerspec is 300 megabits (mb/s) not megabytes (MB/s). That' also the maximum link speed, not the real-world throughput.Can you do this same test over wired ethernet?

sorry I wasn't very clear therethe wireless network adapter on my laptop is 300mbs (GIGABIT LAN & WIRELESS INTEL® ADVANCED-N 6235 (300Mbps) + BLUETOOTH) - im not expecting 300mbps just trying to give a picture of the setup im usingOver a wired connection im getting around 7MB/s read and write speeds

Ok. Since you are getting 7 MB/s in both directions over wired, then slow WiFi read speed must be related to your wifi link.It might be helpful to check the mtu size on the wireless link.try running the windows cmd shell (type cmd in the start bar) and enterping -f -l 1472 NASIPADDRESSIf that fails, try reducing 1472 down to the largest value that works, and let us know what it is.

im not expecting blistering performance, im just very confused why over a wireless connection I can write 3 x faster to the nas than read from it?

Pinging readynas [192.168.0.2] with 1472 bytes of data:Reply from 192.168.0.2: bytes=1472 time=12ms TTL=64Reply from 192.168.0.2: bytes=1472 time=10ms TTL=64Reply from 192.168.0.2: bytes=1472 time=13ms TTL=64Reply from 192.168.0.2: bytes=1472 time=10ms TTL=64Ping statistics for 192.168.0.2: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),Approximate round trip times in milli-seconds: Minimum = 10ms, Maximum = 13ms, Average = 11ms- under the console for my router MTU is set to 1500 (range I can set is between 1 - 1500)Please excuse my lack of networking knowledge, im an Oracle DBA by trade - this is way out of my comfort zone :)

Read Speed 3 x Slower than Write!!?

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StephenB
Guru - Experienced User
Apr 24, 2013
-your wireless routerspec is 300 megabits (mb/s) not megabytes (MB/s). That' also the maximum link speed, not the real-world throughput.

Can you do this same test over wired ethernet?
anynamewilldo85
Aspirant
Apr 24, 2013
sorry I wasn't very clear there

the wireless network adapter on my laptop is 300mbs (GIGABIT LAN & WIRELESS INTEL® ADVANCED-N 6235 (300Mbps) + BLUETOOTH) - im not expecting 300mbps just trying to give a picture of the setup im using

Over a wired connection im getting around 7MB/s read and write speeds
StephenB
Guru - Experienced User
Apr 24, 2013
Ok. Since you are getting 7 MB/s in both directions over wired, then slow WiFi read speed must be related to your wifi link.

It might be helpful to check the mtu size on the wireless link.

try running the windows cmd shell (type cmd in the start bar) and enter

ping -f -l 1472 NASIPADDRESS

If that fails, try reducing 1472 down to the largest value that works, and let us know what it is.
anynamewilldo85
Aspirant
Apr 24, 2013
im not expecting blistering performance, im just very confused why over a wireless connection I can write 3 x faster to the nas than read from it?
anynamewilldo85
Aspirant
Apr 24, 2013
Pinging readynas [192.168.0.2] with 1472 bytes of data:
Reply from 192.168.0.2: bytes=1472 time=12ms TTL=64
Reply from 192.168.0.2: bytes=1472 time=10ms TTL=64
Reply from 192.168.0.2: bytes=1472 time=13ms TTL=64
Reply from 192.168.0.2: bytes=1472 time=10ms TTL=64

Ping statistics for 192.168.0.2:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 10ms, Maximum = 13ms, Average = 11ms

- under the console for my router MTU is set to 1500 (range I can set is between 1 - 1500)

Please excuse my lack of networking knowledge, im an Oracle DBA by trade - this is way out of my comfort zone :)
StephenB
Guru - Experienced User
Apr 24, 2013
It's not the NAS. If it were, you'd see the same issue wired.

If the wifi link didn't support the full ethernet MTU, than you would get packet fragmentation on the wifi downlink. That can hurt performance. But that is not happening on your link.

How big is your test file?
anynamewilldo85
Aspirant
Apr 24, 2013
tested it with different sizes, ranging from 4GB to 20MB - same speeds

Iv also tried using LAN Speed Test (based on a google search) this shows the same read / write speeds so it all looks consistent .... consistently pants :)
anynamewilldo85
Aspirant
Apr 24, 2013
Sorry about the formatting :

LAN Speed Test Results (04-24-2013 at 21:26:47)
Computer Name: xxxxxx IP Address : xxxxxxxxx Folder : \\Readynas\nas_data
---Writing--- ---Reading---
Packet length : 20,000,000 20,000,000
Time to complete: 4.4521776 11.6815912
Bytes per second: 4,492,184 1,712,096
Bits per second : 35,937,472 13,696,768
Mbps: 35.9374720 13.6967680

taken from LAN Speed test (wireless connection)
StephenB
Guru - Experienced User
Apr 24, 2013
20 MB is too small, as caching interferes with the measurements.

Do you have another PC? Just wondering if you could do a Wired PC->Wireless PC lan speed test.
anynamewilldo85
Aspirant
Apr 25, 2013
im afraid not..

typical file size im transferring is about 1.5gb ... same speeds

I just don't get it, how can wireless read by 3 times slower than write