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With this feature enabled, overall write and read speed should be improved. Also, robustness will be improved for specific cases. However, more RAM will be consumed.
RAM usage = <Nbr of blks on device> / 8 octets
The result should be rounded up.
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If, for example, the value is 4, each time a specific updated sector is requested, the NAND translation layer must search the sector in a group of four sectors. Thus, if the update block metadata cache (FS_NAND_CFG_UPDATE_BLK_META_CACHE_EN) is disabled, four sectors must be read from the device to find the requested sector. The four entries will instead be read from the cache, if it is enabled. If the value is set to 0, the table will be disabled completely, meaning that all sectors of the block might have to be read before the specified sector is found. If the value is 1, the table completely specifies the location of the sector, and thus no search must be performed. In that case, enabling the update block metadata cache will yield no performance benefit.
RAM usage = <Nbr update blks> x
(log2(<Nbr secs per blk>) - log2(<Subset size>) x
<Max associativity> /
8 octets
The result should be rounded up.
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