"OneDrive Is Updating Files" never ends and has high CPU
I have two machines where one has a large bunch of files (ca. 360 GB) while the other machine has only a small fraction of them downloaded. After reaching some point OneDrive does stop syncing anything. When looking at the machine with high CPU I find that most time is spent in KernelBase.dll!LCMapStringW by the sync engine. Procmon and ETW shows what happens: Enumerate a file on my drive Call LCMapStringW with the file name read/write SyncEngine-2020-08-03.2209.25372.179.aodl Goto 1 Between each file enumeration ca. 2.5s! are spent in LCMapStringW and sync engine. That is an insane amount of CPU to walk through the file system. The aodl file seems to be some encrypted SQL database which I cannot read. Has OneDrive for business scalability issues with many small (ca. 10K) files?