AX88 - RAM Usage - how much is normal?

[Bamsefar]

So I have a AX88, however it uses 729 MB of RAM after reboot - is this normal? I think something eats something or something?

 

[skeal]

So I have a AX88, however it uses 729 MB of RAM after reboot - is this normal? I think something eats something or something?

That is normal and you should likely read this site to put your mind at ease. www.linuxatemyram.com

 

[Bamsefar]

Yeah I know how Ram on a Linux System works. However what I had the last couple of days are 99% Ram usage and when that happens my WiFi gets none responsive, and all wireless devices can not reach Internet.

So after a cold reboot, I noticed 729 MB of ram used, and we'll Ax88 has 1024 MB and my previous 88AC had half and never had any Ram usage issues.........

 

[RMerlin]

If you use a USB disk, the kernel will fill up available RAM with buffered data. That buffer will be released if more important memory requests are made.

 

[Elmer]

So I have a AX88, however it uses 729 MB of RAM after reboot - is this normal? I think something eats something or something?

Exactly what I'm seeing. Problem was, before 384.14 it would drift up to 99% and freeze. Had to reboot on a daily basis. With 384.14 it drifts to 99% and keeps on truckin'. I believe Merlin said something about a memory leak in the Asus NTP server code that was recently fixed, and indeed I use the NTP server.

 

[Makaveli]

Its normal.

I generally see memory usage in the 67-75%.

The scripts i'm running in my sig are on a SSD connected via usb 3 port in the back.

 

[Bamsefar]

Well I do have two USB disks attached:
1) Samsung T5 SSD for swap and all that - can't remove that one....
2) 4TB 3.5" Drive for all movies and music - it is not supposed to be attached to my AX88, however for some time it has been.

I am not sure about why it uses so much after boot. Yes after +10h I am still at 732MB - and that is of no problem. Linux, and UNIX for that matter, does not get into problems just because memory is used. When I worked as Sysadm on SunOS installations back in the 1995 or so, we had a rule of never go over 80% usage since that could get the server into problems... Never mind that old part.

What I know is happening now after some investigation is that I have decided to move my 4TB disk to well a 4TB SSD, and running copy over network to the server that has the 4TB SSD attached. Now that drives up the load, of course, on the router (the server has way more power so well it does not care kind of) both CPU, RAM and Network traffic of course. Nothing new there.

However what I seem to see is that after about 500GB (out of about 1.2TB) of transfer the WiFi kind of goes none responsive. This is also when I seem to notice that the swap is over cramped.

The end result: Don't use USB disc on the router if you have any intention of moving files above 1GB or so - it will, sooner or later, kill WiFi. I guess that WiFi seems to be depending on RAM, and well there simply is no RAM left ;-) Don't get me wrong, this is most likely by design or lack of design - so nothing to have to do with RMerlin at all.

However one thing is still needed to be sorted: I run Speedcheck and Ping modules in AMTM, and well how much RAM does that use? The WEB Gui is changed by those two modules, and well they are placed in RAM as I understand this, so I will check later today if removing those two modules will release RAM after boot (and startup of AMTM and stuff).

Thanks for all help!

 

[RAH-66]

Don't use USB disc on the router if you have any intention of moving files above 1GB or so - it will, sooner or later, kill WiFi.

its joke? every day my ip wifi cams write dozens of gigabytes on ssd

 

[Val D.]

The end result: Don't use USB disc on the router if you have any intention of moving files above 1GB or so - it will, sooner or later, kill WiFi. I guess that WiFi seems to be depending on RAM, and well there simply is no RAM left ;-) Don't get me wrong, this is most likely by design or lack of design - so nothing to have to do with RMerlin at all.

Same thing happens on RT-AC86U. Low RAM condition kills essential services at some point.
https://www.snbforums.com/threads/s...-cat-6-cable-with-rt-ac87u.59444/#post-518441

 

[Bamsefar]

its joke? every day my ip wifi cams write dozens of gigabytes on ssd

Nope! Maybe more than 1GB but for sure 500GB will get me into problems with my router. So yes you might get alot more than 1GB but for sure less than 500GB.

 

[Bamsefar]

As end-info kind of: Removed my 4TB 3.5" USB drive, uninstalled the AMTM modules I did not need (connection monitor and speedcheck). End result: 568MB of RAM after reboot and all.

 

[Val D.]

(connection monitor and speedcheck)

spdMerlin is not advisable for ISP >100Mbps, eats too much of RAM. But removing some stuff won’t solve Samba server issue, your router will most likely crash with large transfers again, just a bit later.

 

[Bamsefar]

Yes of course - that is why I moved the drive from my router.

But my first questions was, and well maybe still is, how much RAM does it really take to start the router up?

 

[Marin]

I only have Diversion, Skynet, ntpMerlin and uiDIV stats installed and my RAM is at 97%. A reboot brings it down to 72% but then in a day or so it goes up to 97%. I have to admit, this is the first time that my RAM usage has been up this high.

 

[Val D.]

Unfortunately, even with the latest official Asuswrt firmware, if all TrendMicro features are enabled RT-AC86U can’t survive 10 days with no reboot. The RAM usage creeps up to 95% and things go downhill. Usually first stops working Traffic Analyzer, then WebUI becomes unresponsive or unavailable. I don’t know how long ASUS will tolerate buggy TrendMicro firmware components. And how long it is going take to fix other non working or partially working components, like Samba server mentioned above. Who was the programmer who decided to allocate all available RAM to buffers, crashing other main services in the process?

 

[dosborne]

I've never seen my RT-AX88U use more than 53% ram. (CPU rarely above 5%)

No scripts, no USB devices. Just basic router functions and VPN.

 

[L&LD]

Almost exactly 5 days on 384.14 Beta2 on RT-AC86U and RAM is 33MB 'free' with 94% utilized. This is normal for my network environment since I first bought and deployed the router closer to the beginning of this year.

In Tools, SysInfo:

Buffers are at 2MB
The Cache is at 110.5MB
and Swap is at 21MB out of 2GB size.

No issues, stable, fast and working with all the scripts indicated in my signature below. Running on a 256GB USB drive in USB 2.0 mode in the USB 3.0 port with Ext4 and journaling enabled.

 

[Val D.]

No scripts, no USB devices. Just basic router functions and VPN.

This is how I run my own RT-AC86U too. No TrendMicro data collection services, I have better replacements for what scripts do, VPN runs on x86 hardware clients better. Doing experiments with another RT-AC86U with 81351 and the results so far are not very promising. The most stable firmware to date is probably 45717. I don't know how Eric still manages to build something usable on top of this software mess.

and Swap is at 21MB out of 2GB size.

Forget about this swap. It's there just in case and to make you feel good. There is no need for it for anything else. Even with all scripts installed and running it's rarely used for anything. It's completely unusable as a system swap on a USB stick, partially usable on a SSD with USB 3.0 mode activated. It's like attaching "fast" 1.44MB Floppy drive from 1986 to a 2019 computer and expecting increased performance as a result.

Running on a 256GB USB drive in USB 2.0 mode in the USB 3.0 port with Ext4 and journaling enabled.

Waste of a USB stick. First, you don't need 256GB to run scripts. If you're thinking about cells wear leveling, forget about it. In majority of cases the failing part in a USB stick is the controller, not the actual memory chip. No matter what file system you have, data is gone. Second, 2GB swap file is completely unnecessary. No matter how you torture the router you won't see anything above 500-600MB used, and only on a SSD. After that something crashes and stops working. If you worry about cells wear again, well... continue worrying, because a USB stick is the worst place to have a swap file on. Good news is the one you have is non functional, so don't worry too much. What you have to worry about more is the heat. The cheap design allows USB ports area to heat up quite a bit, not good for any USB stick connected there. Some SanDisk USB sticks generate a lot of heat and combined with the router's heat the result is melted plastic. Haven't seen this? Oh, it's an awesome example in design and engineering.

 

[L&LD]

For the rest of the forum users here:

As has been mentioned many times: use a USB drive on an extension USB cable. Keeps it cooler and more stable too.

I don't monitor swap file usage, this was just a point in time metric after the router had been used for about 5 full days on the new firmware.

As for the 256GB USB drive size? It was an extra I could use, so no need to go buy an SSD to run at USB 2.0 speeds.

 

[Frankflash]

Unfortunately, even with the latest official Asuswrt firmware, if all TrendMicro features are enabled RT-AC86U can’t survive 10 days with no reboot. The RAM usage creeps up to 95% and things go downhill. Usually first stops working Traffic Analyzer, then WebUI becomes unresponsive or unavailable. I don’t know how long ASUS will tolerate buggy TrendMicro firmware components. And how long it is going take to fix other non working or partially working components, like Samba server mentioned above. Who was the programmer who decided to allocate all available RAM to buffers, crashing other main services in the process?

Trend Micro features are full of bloat and a ram hogg Asus needs to dump Trend Micro because their stuff is alway ram heavy