I am looking for a new hardware for my mesh network. Unfortunately BBBW was unsufficient in terms of maximum mesh node-number, according to the my test. There is module called Carambola2. There is one drawback about this module that it has low flash/RAM memory size. It has 16MB flash and 64MB RAM. I'm worried about low memory will limit the number of mesh nodes. Adding a new node into the mesh will use extra memory in RAM? If so, I think that 64MB RAM would be problematic. Carambola2 use AR9331 chipset. There are many routers/Access points used AR9331 chip. Is there any experience about the Carambola2 mesh-network? At most how many nodes can you build a mesh-network by using Carambola2?
As there are plenty of devices with at least 16 MB of flash and 128 MB of RAM at reasonable prices (starting at under US$20 for single-band devices), it's hard to recommend anything less than that. There is reasonable evidence that at least 256 MB of RAM is needed for stable operation of units with two or more ath10k radios. I would be concerned about 64 MB of RAM in any application. From https://openwrt.org/supported_devices/432_warning
64 MB may still have issues with stability, depending on your hardware and use cases
At least from the photos, the Carambola 2 isn't FCC certified (though others in the line bear suggestion that they have been). If a commercial endeavor, that might be problematic.
There is AR9331 chip on the Carambola2. I think that memory limitation is caused by AR9331 address space. Unfortunately, It is seen that AR9331 chip can address up to 16MB Nor Flash memory and up to 64MB DDR2 RAM memory (for a single device). I dont know whether memory usage (both Flash and RAM) is increased while adding new node into the mesh-network (802.11s). What do you think, Sir?
I think 64 MB of RAM is going to bite you now or in a year or two, as the kernel and third-party application footprints (such as hostapd) continues to grow. You can't stay on older kernels as they will no longer be secure as they age.
ath10k is the driver for most current and recent generations of Atheros Qualcomm wireless chips and subsystems. The ath9k driver is for generally much older generation devices.