RT-AC68U Slow USB 3.0 speeds

[RMerlin]

For a "real" USB 3.0 drive from Kingston, look at their DataTraveler Ultimate G3 3.0. I got a pair of them a few months ago as NCIX has a discount on them. They'll break the 100 MB/s barrier.

 

[Rares Oltean]

Thanks for the tip @RMerlin!
I was just looking at SanDisk Cruzer Extreme 64GB, USB 3.0, that reads with 245 MB/s and writes with 190 MB/s.
But now that you mentioned Kingston's DataTraveler Ultimate, I found Kingston HyperX Savage, 64GB, USB 3.1/3.0, that reads with 350 MB/s and writes with 180 MB/s, and is also 25% cheaper than SanDisk. So, most likely, I'm gonna go with Kingston, even though the ASUS RT-AC68U may not be able to reach even half of those speeds.

Also thank you so much for ASUSWRT-Merlin! It really brings out the best in my router and adds a lot of functionality that I need and that's missing from the original firmware from Asus.

 

[Wutikorn]

I have AC68U running AsusWRT-Merlin 380.60 beta 2, but I can only get up to 11-12MB/s read speed through LAN(almost 100% CPU usage on one of the cores). Is that normal? Does NAT Acceleration have any effect on transfer speed?

 

[anon2015]

I have AC68U running AsusWRT-Merlin 380.60 beta 2, but I can only get up to 11-12MB/s read speed through LAN(almost 100% CPU usage on one of the cores). Is that normal? Does NAT Acceleration have any effect on transfer speed?

AC68P here. I get 25-30 MB/s when transferring files from my SD to my PC wirelessly and both cores sit at 100%. I am on Asus Firmware 3.0.0.4.380.3264 NAT set to auto. Its much slower than I expected but good enough since I mostly use it to stream music. I havent taken the time to figure out the real bottleneck, but yours seem too slow.

 

[Wutikorn]

AC68P here. I get 25-30 MB/s when transferring files from my SD to my PC wirelessly and both cores sit at 100%. I am on Asus Firmware 3.0.0.4.380.3264 NAT set to auto. Its much slower than I expected but good enough since I mostly use it to stream music. I havent taken the time to figure out the real bottleneck, but yours seem too slow.

I just realized that the cable from my router to my PC is not so good, even though it is CAT 5E. That's why I can only get about that speed. But to estimate it, if both cores sit at 100%, it should be around your speed. Will the whole system be laggy if you transfer files and both cores sit at 100%?

 

[anon2015]

Will the whole system be laggy if you transfer files and both cores sit at 100%?

I notice a slight delay when accessing or using the routers UI. Otherwise I can stream video, music and browse on multiple devices while doing the transfer and notice no negative impact on the network. I have less than 10 devices connected at any time.

 

[mjp93]

I have AC68U running AsusWRT-Merlin 380.60 beta 2, but I can only get up to 11-12MB/s read speed through LAN(almost 100% CPU usage on one of the cores). Is that normal? Does NAT Acceleration have any effect on transfer speed?

I having AC68U:
on stock and 380.59:
Getting upto 11MB/s (R) & 7MB/s (W) similar on both wired and wireless.

On wireless the speed sometimes drops to 4MB/s (R).

Using USB 3.0 HDD , wired pc and Nexus device as for transfer.

I was expecting a speed of around 50MB/s as per other users claim but still haven't achieved yet.

Anyone else with this problem?

 

[qBot]

It seems to me that besides the slow USB 3.0 problem there's a bigger "problematic torrents" problem. I quickly gave up on trying to use the download master (merlin doesn't help with that), so I ended up hooking my 2 TB drive to the router via USB 3.0 (let's call it WiFi-HDD) and just running uTorrent on my laptop with download location set to that drive. I've got 350 Mbps from my ISP, so an average proper download speed would anywhere from 10 to 30 MB/s. And that is what I get when I download directly to my laptop using 5 GHz wireless. But things change when I try to download to the WiFi-HDD: it starts to accelerate from 0 to 5 MB/s quickly, then after about 5-15 sec it drops, sometimes saying that WiFi-HDD is no longer accessible. Sometimes that rise/drop can repeater a couple of times (see the pic below)... But in about 80% of cases it's unbearable. In the other 20% it maintains a constant speed of 5 to 10 MB/s. Mostly around 5 When I try to copy a file to WiFi-HDD I get up to 20-23 MB/s, but as noted in other posts above the speed randomly varies according to the routers "mood".

Why the hell is AC68U having such problems with maintaining a constant write speed for some streaming data (like torrent) and not having any problems (besides being slow) for a single copying of a large file?.. I'd be glad to have at least 10 MB/s of constant download speed when I set my download location to WiFi-HDD. Is that to much I ask from AC68U?.. Is there any trick that could help?..

 

[Wutikorn]

@qBot, what is the speed of your laptop 5GHz wireless? Has you tried transferring the same thing to LAN? It could be that your laptop wireless card is not up to the task. Also check what is the percent usage of CPU when you are getting each of the speed you benchmarked. If CPU is not above 75%, and RAM usage is not above 90%, then you might want to check for wireless problem

 

[qBot]

@qBot, what is the speed of your laptop 5GHz wireless? Has you tried transferring the same thing to LAN? It could be that your laptop wireless card is not up to the task. Also check what is the percent usage of CPU when you are getting each of the speed you benchmarked. If CPU is not above 75%, and RAM usage is not above 90%, then you might want to check for wireless problem

Laptop to router speed is 500+ Mbps, so that's not a problem at all (I've upgraded my card a few years ago). If a stop the torrent and copy a file via LAN, I get the same figure. Suppose the torrent was lagging at mere 5 MB/s, the file copy speed would be 5 MB/s as well. But sometimes those figure could jump up to 10 or 15 MB/s with no apparent reason.

So the bottleneck is definitely the routers ability to write files onto HDD. And that write speed oscillate with a characteristic time of 1-5 minutes...