The format of JSON keystores created by the Go-Ethereum Geth executable are slightly different format than the JSON keys created on the MyEtherWallet website. Can anyone explain the differences? I have found that the Geth executable unlocks the MEW format much faster in an embedded/low resource environment. One of the things I noticed was the "n" value in kdfparams is much lower in MEW keys than GO-Ether Geth key format.
The format used for this wallets allows choosing different algorithms, commonly used are scrypt and PBKDF2.
Likely your wallet use scrypt, in that case "n" controls how much temporary memory will be used. A larger "n" means it will take longer to open your wallet, but it also means it will be more secure.