@imk82 About filenames: Last time I’ve tested with cyrillic (and other specially encoded characters) on Android, syncthing had a message on the web UI if it doesn’t support the encoding of some files. I’d suggest you check out the web UI. If there are no orange popups about the encoding, I’ll consider that no problem.
my SD Card is not as “fast” as stated in the initial Post. Its big, but not fast (200Gb Sand Disk Ultra).
with an USB Stick connected via usb-c and another SD Card which is really fast (San Disk Extrem Pro) things are running stable (most of the time, its not the same as with the other folders with smaller files).
Syncthing seems to have a problem, if IO is limited. I tried the limits for the Network (Incoming/Outgoing), setting them e.g. to 1000 doesn’t solve the problem.
because the root cause is not fully tracked down, it’s hard to say if a fix within Syncthing is possible. From my point of view the Idea should be to add a option to throttle down Syncthing while it accesses storage. But maybe thats impossible.
I will do further research if I find time, but for now it is usable from my side.
If it starts throwing IO errors, there is not much we can do. A lot of the branded SD cards are actually cheap knockoffs with branding, which could also be the potential underlying cause.
I don’t know if real errors in the meaning of read / write errors occur or if its a kind of buffering issue. What I can say is that the same SD Card runs fine if I Copy the whole content via FTP to the phone. It is as the topic says…weired.
My next step is to buy a SD Card which is big AND fast.