- Fri Aug 21, 2020 4:56 am
#88410
If it's using TLS, you'll end up with very little RAM anyway?
Moderator: eriksl
- Sat Aug 22, 2020 12:20 am
#88419
I'm using TLS and am managing with a buffer size of 4096, which works fine. I still have quite a bit of free RAM
- Sat Aug 22, 2020 1:06 am
#88420
Yes, but - unfortunately - every Async fan/user is stuck with AXTLS (no BearSSL for now) so no MFLN option...
- Sat Aug 22, 2020 8:18 am
#88422
How do you guys check how much RAM you actually have left?
I learned that LWIP ("out of the box") uses quite some amount of RAM transiently, so even if you think you have, say, 3 kbytes left, sending or receiving of frames starts to fail.
So I configured LWIP to only use "static" memory (as a matter of fact I do not use "heap" memory anywhere) and then I saw that amount of "available" memory shrink considerately.
I think that on a tight-on-RAM microcontroller (without virtual memory) should not use a heap (or much stack) anyway, because it becomes unpredictable how much is really used and there may come a moment you're left with none, probably crashing the whole thing.
I learned that LWIP ("out of the box") uses quite some amount of RAM transiently, so even if you think you have, say, 3 kbytes left, sending or receiving of frames starts to fail.
So I configured LWIP to only use "static" memory (as a matter of fact I do not use "heap" memory anywhere) and then I saw that amount of "available" memory shrink considerately.
I think that on a tight-on-RAM microcontroller (without virtual memory) should not use a heap (or much stack) anyway, because it becomes unpredictable how much is really used and there may come a moment you're left with none, probably crashing the whole thing.
