Network HDD R/W speeds are slower despite Gbps connectivity ... Why ?

[ahmadka]

Hi guys ... I have an issue which I can't figure out ..

I have a 5 Tb HDD (NTFS, USB 3.0 compatible). When I connect this to a PC directly (tried on both USB 3.0 and USB 2.0 computers), the read and write speeds are about 33 ~ 37 MB/sec

However, when I connect the HDD directly to my ASUS RT-N66U (374.41 Merline FW), the r/w speeds drop to about 7 ~ 15 MB/s

Why is this ?

Here is my network layout:

HDD < --> ASUS RT-N66U <--- 1Gbps connection --> TP-Link TL-SG1008D <--- 1Gbps connection --> Laptop

1 Gbps connection is capable of 125 MB/s roughly, so then where's the problem ?

To measure the speeds, I used 5 GB dummy files. I also read and wrote to/form the HDD using both Windows and LAN Speed Test. The results shown in the latter where a little lower than what the former showed.

I'm having speed issues .. I need the drive to have a higher R/W speed because it's causing problems for me.

Here are the detailed results:

HDD <-> ASUS Router <-> Switch <-> Laptop Write (Windows): 11.2 MB/s
HDD <-> ASUS Router <-> Switch <-> Laptop Read (Windows): 15.3 MB/s
HDD <-> ASUS Router <-> Switch <-> Laptop Write (LAN Speed Test): 9.6 MB/s
HDD <-> ASUS Router <-> Switch <-> Laptop Read (LAN Speed Test): 10.56 MB/s
HDD <-> Laptop (USB 3.0) Write: 28 MB/s
HDD <-> Laptop (USB 3.0) Read: 33 MB/s
HDD <-> Generic PC (USB 2.0) Write: 37 MB/s
HDD <-> Generic PC (USB 2.0) Read: 33 MB/s

 

[thiggins]

File transfer performance to a USB drive depends on the power of its host's processor. The ASUS router's processor isn't powerful enough to provide the same storage performance as a computer CPU.

 

[john9527]

Never had actually measured my performance, so just for comparison....

Same basic configuration as you, except:

AC68U overclocked to 1200,800
Monoprice switch
Going to desktop computer
Old 5400RPM 2.5" drive in Vantec enclosure attached to USB2 hub to router - formatted NTFS

Used a 18GB VHD for the test....speed measured at about 50% copied

HDD <-> USB2 HUB <-> ASUS Router <-> Switch <-> Desktop Write (Windows): 26.0 MB/s
HDD <-> USB2 HUB <-> ASUS Router <-> Switch <-> Desktop Read (Windows): 29.2 MB/s

Using a USB3 memory stick

USB3 Stick <-> ASUS Router <-> Switch <-> Desktop Write (Windows): 43.6 MB/s
USB3 Stick <-> ASUS Router <-> Switch <-> Desktop Read (Windows): 65.5 MB/s

 

[RMerlin]

Hi guys ... I have an issue which I can't figure out ..

I have a 5 Tb HDD (NTFS, USB 3.0 compatible). When I connect this to a PC directly (tried on both USB 3.0 and USB 2.0 computers), the read and write speeds are about 33 ~ 37 MB/sec

However, when I connect the HDD directly to my ASUS RT-N66U (374.41 Merline FW), the r/w speeds drop to about 7 ~ 15 MB/s

Why is this ?

In addition to what Tim posted, you are also trying to use a USB 3.0 HDD on a device with only USB 2.0 ports. Look at these results for what I get out of an RT-AC87U, which has USB 3.0 ports (and a much faster CPU):

http://forums.smallnetbuilder.com/showpost.php?p=130339&postcount=13

Expect slightly lower results with the RT-AC56/RT-AC68, due to their slightly slower CPU versus the RT-AC87.

If R/W performance is critical, you should really be using a real NAS anyway. The hardware of these routers is optimized for low latency traffic routing, not for high throughput disk sharing.

 

[ahmadka]

Thanks for the input guys ..

Regarding the USB 3.0/2.0, I'm aware that N66U has USB 2.0 ports .. So to rule that out as the reason, I did test transfers using a PC I have which has USB 2.0 ports .. The rates were still above 30 MB/s ..

So I guess the reason is a slower CPU on the router ? Is there something I can do to at least get the rate upto 20 MB/sec at least, other than buying a whole new router ?

 

[noric]

If you overclock you'll get close to 20MB/s read speed.

 

[ahmadka]

I also just tried bypassing the switch (just checking) .. Connected a CAT 6 directly from router to Laptop .. still the same results ..

I'm not sure if overclocking is okay to do yet or not .. I've done it before for gaming PCs, but never tried it on a router, so a little reluctant until I read up ..

What is a NAS ? I don't know much about it. Can I use my existing drive or will I have to buy a new drive ?

 

[RMerlin]

I also just tried bypassing the switch (just checking) .. Connected a CAT 6 directly from router to Laptop .. still the same results ..

15 MB/s is perfectly normal for this router.

I'm not sure if overclocking is okay to do yet or not .. I've done it before for gaming PCs, but never tried it on a router, so a little reluctant until I read up ..

Quite frankly, going from 15 to 17-18 MB/s won't provide any measurable improvement. If you really need better performance, get a real NAS instead of a shared USB disk.

What is a NAS ? I don't know much about it. Can I use my existing drive or will I have to buy a new drive ?

A NAS is a Network Attached Storage. It's essentially a disk drive shared over the network. They start with very basic, single drive connected to a USB port, and can range to very complex devices with multiple disks in RAID, advanced tools such as torrent client, media sharing services, web servers, etc...

Most basic NAS come with their own disks. You can supply your own disks only with more advanced models, which usually start at two disks.

 

[ahmadka]

Ah okay.

Since I already have the drive, I don't want to rebuy that. After a quick Google search, I see there are 'NAS Adapters' which can be used with a normal external HDD. But the two I've seen have a limit to supporting a max of 2 Tb HDD only, whereas mine is 5 Tb :/

Buying a whole NAS doesn't seem right because my use of this shared storage is occasional to rare only.

When I was buying this HDD, I didn't think the Router could be the bottleneck as it was marketed as being an A+++++ router ... Guess I fell to the hype

One question. Instead of buying a NAS, would it be okay to buy another router which has a USB 3.0, and has Gbps connectivity ? I ask because I have to buy another router for my house soon, as maybe I can connect the HDD to that new router instead.

 

[L&LD]

A new router may very well help. Check the charts.


(I think the R7000 is the king of USB transfer speeds).

 

[ahmadka]

A new router may very well help. Check the charts.


(I think the R7000 is the king of USB transfer speeds).

Can you provide me with a link ?

This page doesn't have a USB throughput benchmark:

http://www.smallnetbuilder.com/lanwan/router-charts/view

 

[RMerlin]

Ah okay.

Since I already have the drive, I don't want to rebuy that. After a quick Google search, I see there are 'NAS Adapters' which can be used with a normal external HDD. But the two I've seen have a limit to supporting a max of 2 Tb HDD only, whereas mine is 5 Tb :/

You'll also want to make sure that such adapters would be able to give you good performance. If they are underpowered, they might not be really faster than a router.

Buying a whole NAS doesn't seem right because my use of this shared storage is occasional to rare only.

It's always a matter of need versus budget. There's no shortcut available, you usually get what you paid fore.

When I was buying this HDD, I didn't think the Router could be the bottleneck as it was marketed as being an A+++++ router ... Guess I fell to the hype

Key word here is "router". A router's primary job is to route traffic. Disk sharing is an added feature.

One question. Instead of buying a NAS, would it be okay to buy another router which has a USB 3.0, and has Gbps connectivity ? I ask because I have to buy another router for my house soon, as maybe I can connect the HDD to that new router instead.

See the benchmark results I posted for the RT-AC87U. Expect closer to 50 MB/s with the RT-AC56 or RT-AC68.

 

[RMerlin]

A new router may very well help. Check the charts.


(I think the R7000 is the king of USB transfer speeds).

Both the WRT1900AC (currently the fastest one when it comes to disk sharing, but with other drawbacks) and the RT-AC87U will beat the R7000.

I haven't really looked at the R8000 USB results, these should be on par, if not better than the RT-AC87U, due to its use of Broadcom's SDK7. This will change in the near future however once the RT-AC87U also transitions to SDK7. By then, the RT-AC87U is expected to match the WRT1900AC for USB performance.

 

[john9527]

For another data point...updated my original post using a USB3 memory stick on an overclocked AC68U...

Read = 65.5 MB/s, Write = 43.6 MB/s

 

[Shrmn]

Using a 2010 NAS from Thecus configured on RAID 5 for a total of 4TB of useable space, I get about 40 MB/s write and 65 MB/s read for a single 18GB file transfer over a gigabit connection.

NAS -> RT-AC68U -> D-Link Green 8-port Gigabit Switch -> Win7 Desktop


I think a more practical way to share your drive would be in using an external enclosure with network capabilities (in addition to a USB connection). Get a decent one or as RMerlin said, it might not be really faster than with the router.

 

[ahmadka]

Yeah I guess I'll have to do something like that ..

Thanks for all the help guys !