High RAM Usage RT-AC86U

[DroidST]

Just purchased a RT-AC86U from this weekend's promo pricing.

Installed Merlin 384.8 Beta2 and then did a Restore / Initialize.

I rebooted the router.

I noticed RAM used/usage was at 51% steady and I have not even started config except enabled both radios (and Operation Mode: Wireless router) and changing the Router's IP address. I am connected ethernet to a laptop for config/setup.

After config (except DNS filter clients), RAM usage is at 68% steady (346MB Used | 166MBMB Free | 512MB Total).

My current main router is a RT-AC68R running Merlin 380.59 and RAM usage is 23% steady (57MB Used | 193MBMB Free | 250MB Total).

Both now configured with all Trend Micro/QOS stuff enabled.

Is the high RAM used on the 86U normal (even with after a factory reset)? I hope I don't have to factory reset this again.

EDIT: The 68R has also Traffic Analyzer enabled so that should be taking memory, the 86U has that disabled.

.

 

[JDB]

The graph includes cached RAM which can be considered free. Look at Tools>Sys Info for more details about how RAM is allocated.
I plan to open a ticket with Asus to change the graph to exclude cached RAM as it just makes people think it’s using more than it is.


Sent from my iPhone using Tapatalk

 

[Hawk]

Just purchased a RT-AC86U from this weekend's promo pricing.

Installed Merlin 384.8 Beta2 and then did a Restore / Initialize.

I rebooted the router.

I noticed RAM used/usage was at 51% steady and I have not even started config except enabled both radios (and Operation Mode: Wireless router) and changing the Router's IP address. I am connected ethernet to a laptop for config/setup.

After config (except DNS filter clients), RAM usage is at 68% steady (346MB Used | 166MBMB Free | 512MB Total).

My current main router is a RT-AC68R running Merlin 380.59 and RAM usage is 23% steady (57MB Used | 193MBMB Free | 250MB Total).

Both now configured with all Trend Micro/QOS stuff enabled.

Is the high RAM used on the 86U normal (even with after a factory reset)? I hope I don't have to factory reset this again.

.

High memory usage on this router is perfectly normal, though I do recommend factory reset whenever you move between Asus stock firmware and merlin or vice versa.

 

[DroidST]

Showing 26MB for Cache so I see where 26MB is coming from. However, the 86 has double the memory but is showing much higher percentage (more than double) of the 68R. The 86U is not actually in use, the 68R is.

is 51% RAM usage on the 86U after factory reset normal then?

.

 

[DroidST]

High memory usage on this router is perfectly normal, though I do recommend factory reset whenever you move between Asus stock firmware and merlin or vice versa.

after updating to Merlin's, I did the Initialize which from what I read (RMerlin's post), does Restore plus....

The 68R has also Traffic Analyzer enabled so that should be taking memory, the 86U has that disabled.

51% after Restore (Factory default) seems high. Perhaps someone else will replay once they do a fresh one and load Merlin's Beta2 / Restore.

EDIT: I should have searched this topic (I KNOW BETTER). I see this is normal

Interesting to me though.

.

 

[Hawk]

Showing 26MB for Cache so I see where 26MB is coming from. However, the 86 has double the memory but is showing much higher percentage (more than double) of the 68R. The 86U is not actually in use, the 68R is.

is 51% RAM usage on the 86U after factory reset normal then?

.

Yes, it is perfectly normal. I have fairly vanilla setup and mine is sitting at 53% total usage. If it ease your curiosity, quite bit of portion of ram is use by Broadcom Components for their internal use, mostly wifi radios.

 

[DroidST]

Interesting...

I wish I would have looked at that (or remembered what it was) on the stock installed f/w (3.0.0.4.384.20467) right when I got it.

.

 

[RMerlin]

is 51% RAM usage on the 86U after factory reset normal then?

Yes. The Broadcom environment is much more complex than what is used by the older RT-AC68U. Broadcom reserves 13% or 17% (I forgot the exact number) of RAM for buffers used by various components (like the wifi driver).

 

[cmkelley]

Several people have written long explanations here of what the "used" memory actually means, and the short answer is, a single number doesn't tell you anything of value. Ignore it.

Contrary to popular belief, in the Unix world, "used" memory doesn't mean "not available", it means "holding information the kernel may find useful", with the key word being "may". Some of that "used" memory is in fact unavailable because it is marked as being actively used. Some of that "used" memory is in fact available if needed because the kernel has decided it can simply reload that data in the future if it needs it. The kernel will (hopefully) make intelligent decisions about what memory to discard if a request comes in to allocate more memory than is "free", where "free" means "not marked as used".

My AC86U hovers around 93% to 96% "used", although I do have Diversion, pixelserv-tls, and probably other stuff I've forgotten about running. I do have a swap file, but that is only strictly necessary for I think Diversion when updating. It's currently sitting at 35 MB used, and my "free" memory is at 36 MB.

 

[snakebite3]

I don't understand people's obession with the router RAM usage. Do you not want the RAM to be used? Why do you have if you not going to use it?

 

[kernol]

I don't understand people's obession with the router RAM usage. Do you not want the RAM to be used? Why do you have if you not going to use it?

I have a RT-AC5300 which is also heavy on RAM despite having lots of it [a good thing]. Why do I care? Simply because I have had the experience of my router crashing out when its RAM was fully filled [problem posted elsewhere] - despite a 512Mb swap ... which as it turns out was not being used by the kernel?!

I found the solution to my specific RAM crash problem - [turned out to be a wobbly USB with frequent "dc" error reports on reboot - impacted on the swap file usage it seems]. Nevertheless I continue to monitor from time to time - and where RAM is running really thin - simply reboot to restore normality.

 

[wesbez]

Recently just got mine with the deals on. 69% ram after doing restore and applying settings.

 

[snakebite3]

I have a RT-AC5300 which is also heavy on RAM despite having lots of it [a good thing]. Why do I care? Simply because I have had the experience of my router crashing out when its RAM was fully filled [problem posted elsewhere] - despite a 512Mb swap ... which as it turns out was not being used by the kernel?!

I found the solution to my specific RAM crash problem - [turned out to be a wobbly USB with frequent "dc" error reports on reboot - impacted on the swap file usage it seems]. Nevertheless I continue to monitor from time to time - and where RAM is running really thin - simply reboot to restore normality.

Is RAM crash a common problem for routers? Unless there a bug with memory management I don't think this is a problem users should be concern about. My router's ram usage have been at 88% since the cache option was added and with no swap file. I've not yet experienced a RAM related router crash.

The crash you experience was caused by your USB. If you didn't have a swap file shouldn't the ram management flush the cache?

 

[DroidST]

I don't know what was going on last night after I did most of the config but the 86U wasn't "in use" but was at 68% RAM Usage.

I turned it off for the night and when I powered it back on today around 11:30am, it was at 50-51% RAM Usage from the start. Last night, I just rebooted from the GUI, not powered down with the power switch.

Anyways, the 86U is now in operation as of Noon today (connected to WAN, serving local wired and wireless clients), RAM Usage at 69% - using all of Trend Micro* stuff, DNS filtering, QOS.

Already got a hit attempt on my webserver

AiProtection - Two-Way IPS
Details of a Successfully Protected Event

WEB Microsoft IIS WebDAV ScStoragePathFromUrl Buffer Overflow -1 (CVE-2017-7269)
Severity Level: High
Source: 118.89.222.***

.

 

[pdc]

The graph includes cached RAM which can be considered free. Look at Tools>Sys Info for more details about how RAM is allocated.
I plan to open a ticket with Asus to change the graph to exclude cached RAM as it just makes people think it’s using more than it is.

People such as myself!

Thanks so much for this info. I am running SMB, Diversion, and pixelserv-tls on my AC86U and routinely run at 95%+ used, which I was a little concerned by and wondering if I needed a swap file.

Looking at Tools > Sys Info, 115MB of that is cache -- almost 25%! No swap file needed

C'mon Asus, cached is not the same as used...

 

[curlysir]

My AC86U running 384.8 was at 81% and I came here to see if I could fine any thing about what it should be and what do you know, here it being discussed. Just did a reboot and it came down to 66%. Guess that is not out of line from the comments here.

 

[DroidST]

after reboot, mine will be at 66% as well and seems to be maintaining 71-74% after 3-4 days.

.

 

[Steve2300]

after reboot, mine will be at 66% as well and seems to be maintaining 71-74% after 3-4 days.

Ditto

 

[giracueca]

I see this fact too on mine router. I jump from AC66 that have 256 mbs ram to ac86. Its strange for me. I cant say thats a error, a problem, but is strange for the first time. It remembers Windows. As much ram as you have more that uses.
In both router I have the same services on, but the RAM usage is much differente that I expected. I Agree with the grafics must show ram usage, cached is not the same as used.
But ok...this is just a notice of diferent routers.
The same AC66 with tomato have 90% of ram free by default. A curious case.

 

[Adam Popiel]

I made the same mistake, now i have merlin Firmware Version:384.13 and most services on like vpn qos security samba upnp ftp traffic analyser ddns and a ssd in the usb3.0 slot and now mine runs on 95% !! does anyone know if this is normal