The size of some in-memory caches can be reduced. As caches trade off memory usage for performance, usually reducing these have a negative effect on performance.
-`-dbcache=<n>` - the UTXO database cache size, this defaults to `450` (`100` before 1.0.15). The unit is MiB (where 1 GiB = 1024 MiB).
- The minimum value for `-dbcache` is 4.
- A lower dbcache make initial sync time much longer. After the initial sync, the effect is less pronounced for most use-cases, unless fast validation of blocks is important such as for mining.