TPLink RE450 going out of memory 19.07.3

Since the upgrade to openwrt 19, my RE450 V1 started having more problems and I have to reboot it every few days. With openwrt 18, I observed similar issues but they were enough rare to not bother investigating.
Now with rel 19 I noticed that LUCI web interface were not accessible from my browser, while ssh connections are still fine. After some testing, I discovered that processes were killed because of out of memory conditions. When memory gets very low, even logread is unable to work.

I tried a factory reset and a new setup, but the condition is the same. I'm using the RE450 as access point connected to my DSL router.

TIA,

Yuri

Having the same problem, I'm on [19.07.5].
I think memory is not initialised properly.

root@OpenWrt:~# df -h
Filesystem                Size      Used Available Use% Mounted on
/dev/root                 2.8M      2.8M         0 100% /rom
tmpfs                    29.1M    276.0K     28.9M   1% /tmp
/dev/mtdblock4            1.7M      1.1M    636.0K  63% /overlay
overlayfs:/overlay        1.7M      1.1M    636.0K  63% /
tmpfs                   512.0K         0    512.0K   0% /dev
root@OpenWrt:~# free -h
              total        used        free      shared  buff/cache   available
Mem:          59640       35836       17664         276        6140        9092

I can only see 64MB RAM, I thought like all v1 models have 128MB of RAM
dmesg:

root@OpenWrt:~# dmesg
[    0.000000] Linux version 4.14.209 (builder@buildhost) (gcc version 7.5.0 (OpenWrt GCC 7.5.0 r11257-5090152ae3)) #0 Sun Dec 6 07:31:03 2020
[    0.000000] MyLoader: sysp=69296996, boardp=69696996, parts=69696996
[    0.000000] bootconsole [early0] enabled
[    0.000000] CPU0 revision is: 00019750 (MIPS 74Kc)
[    0.000000] SoC: Qualcomm Atheros QCA9558 ver 1 rev 0
[    0.000000] Determined physical RAM map:
[    0.000000]  memory: 04000000 @ 00000000 (usable)
[    0.000000] Initrd not found or empty - disabling initrd
[    0.000000] Primary instruction cache 64kB, VIPT, 4-way, linesize 32 bytes.
[    0.000000] Primary data cache 32kB, 4-way, VIPT, cache aliases, linesize 32 bytes
[    0.000000] Zone ranges:
[    0.000000]   Normal   [mem 0x0000000000000000-0x0000000003ffffff]
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000000000-0x0000000003ffffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x0000000003ffffff]
[    0.000000] On node 0 totalpages: 16384
[    0.000000] free_area_init_node: node 0, pgdat 804ecd50, node_mem_map 81000020
[    0.000000]   Normal zone: 128 pages used for memmap
[    0.000000]   Normal zone: 0 pages reserved
[    0.000000]   Normal zone: 16384 pages, LIFO batch:3
[    0.000000] random: get_random_bytes called from 0x804f0740 with crng_init=0
[    0.000000] pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768
[    0.000000] pcpu-alloc: [0] 0
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 16256
[    0.000000] Kernel command line:  board=RE450 mtdparts=spi0.0:128k(u-boot)ro,6016k(firmware),64k(partition-table)ro,64k(product-info)ro,1856k(config)ro,64k(art)ro console=ttyS0,115200 rootfstype=squashfs noinitrd
[    0.000000] PID hash table entries: 256 (order: -2, 1024 bytes)
[    0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
[    0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
[    0.000000] Writing ErrCtl register=00000000
[    0.000000] Readback ErrCtl register=00000000
[    0.000000] Memory: 59320K/65536K available (3954K kernel code, 193K rwdata, 516K rodata, 320K init, 212K bss, 6216K reserved, 0K cma-reserved)
[    0.000000] SLUB: HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[    0.000000] NR_IRQS: 51
[    0.000000] Clocks: CPU:720.000MHz, DDR:600.000MHz, AHB:200.000MHz, Ref:40.000MHz
[    0.000000] clocksource: MIPS: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 5309056796 ns
[    0.000007] sched_clock: 32 bits at 360MHz, resolution 2ns, wraps every 5965232126ns
[    0.008308] Calibrating delay loop... 358.80 BogoMIPS (lpj=1794048)
[    0.074984] pid_max: default: 32768 minimum: 301
[    0.080080] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes)
[    0.087124] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes)
[    0.096464] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
[    0.106966] futex hash table entries: 256 (order: -1, 3072 bytes)
[    0.114426] NET: Registered protocol family 16
[    0.120338] MIPS: machine is TP-LINK RE450
[    0.126543] registering PCI controller with io_map_base unset
[    0.132847] ar724x-pci ar724x-pci.1: PCIe link is down
[    0.138315] registering PCI controller with io_map_base unset
[    0.394495] PCI host bridge to bus 0000:00

I solved my problems using the current snapshot which is built using ATH79 driver.

Yuri

Can you tell me which HW version you have and the snapshots you used?

I have UK v1.0 and used the following images:

http://downloads.openwrt.org/releases/19.07.5/targets/ar71xx/generic/openwrt-19.07.5-ar71xx-generic-re450-v1-squashfs-factory.bin
http://downloads.openwrt.org/releases/19.07.5/targets/ar71xx/generic/openwrt-19.07.5-ar71xx-generic-re450-v1-squashfs-sysupgrade.bin

go to https://chef.libremesh.org/, select snapshot and enter RE450 in the box on the left, select V1; you will get a download link (select SYSUPGRADE)

Yuri

Snapshot download links for RE450 v1

The builds from https://chef.libremesh.org/ are already including Luci.

regards,

Yuri