What does cache value signifies in UpdateTip log messages? UpdateTip: new best=0000000027effeeafbf56c6c9de19f7d8f5b96227b2b4e85c6f6033220866f0d  height=221  log2_work=39.298291  tx=46374  date=2015-11-06 12:02:46 progress=1.000000  cache=3.0MiB(10114tx)


What is the significance of cache=3.0MB in above mentioned UpdateTip log drom debug.log ?
It's describing how much of the allocated UTXO cache you are using. You can adjust how much maximum memory Bitcoin Core uses for this and others with the dbcache parameter, the higher the limit in megabytes the higher the performance to a certain degree.