One of our customer doesn't allocate more than 80GB on C: Drive on any server however in Filesystem Report it's reported as 81.x GB for all servers. And the same issue is being reported for all the other filesystems where the difference is huge in terms of actual allocation.
When we looked in to the issue we found out OBR collecting FS_MAX_SIZE from OM Coda metric which is in Binary but OBR calculates this as a Decimal value. This resulted incorrect/wrong data reported on SM reports.
Below are some technical details:
1 Kilobyte is equal to 103 bytes = 1000 bytes in decimal (SI). – Base 10 method (0-9 decimal system)
1 Kilobyte is equal to 210 bytes = 1024 bytes in binary. – Base 2 method (0 and 1 which are called Bits)
Technically computers don't work in Base-10 but rather it works in binary, that is Base-2, they only use two values: 0 and 1. However, NO one calculates in Base-2. Computers are used to perform calculations that people enter in Base-10 or decimal.
C:\Users\sas-aortega>wmic logicaldisk get size,caption