TDBSTore: skip data CRC when building RAM table #15514
Merged
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Summary of changes
Problem: The build_ram_table() function of TDBStore loops over every entry, calculates the checksum and compares them to the stored checksum in the entry header to ensure integrity. For larger TDBStores (e.g. 8 MiB or more) in external single-SPI flash devices this check can take very long, thus rendering it unusable in some cases.
Solution: The suggested solution skips the time consuming CRC of the data. After reading the key and calculating its CRC, it sets next_offset to the beginning of the next entry, thereby skipping the data. While this skips the integrity check, it significantly reduces the initial building of the RAM table.
The data CRC can be enabled or disabled with a compiler flag.
Contribution is provided on behalf of BIOTRONIK.
Impact of changes
Migration actions required
Documentation
None
Pull request type
Test results
Tests run at our company show full functionality. The RAM table for existing TDBStores with up to 1000 entries is correctly built.
Reviewers