I am trying to do a fast sync using
geth --fast but I am getting this message:
blockchain not empty, fast sync disabled
How can I empty the blockchain to allow for fast sync?
To remove your blockchain with geth, run:
--fast but you probably also need
--jitvm may also help). Without it, you are running with the default which is
A 50% speed increase is possible just by increasing the cache.
If you are starting from the beginning, use:
geth --fast --cache=1024 --jitvm
Depending on your RAM, you can also try with higher values, like
The number after
--cache= is the amount of memory allocated to the task of downloading the blockchain!!
Mac: ~/Library/Ethereum Linux: ~/.ethereum Windows: %APPDATA%/Ethereum
chaindata subdirectory that you find.
geth --fast --cache=1024 for a recommended way to sync the chain quickly (don't forget to use a bigger
--cache with a value like 1024, otherwise the default is 16, and it won't sync as quickly).
geth removedb is the simplest way to delete the blockchain in Geth.