[Ethereum] miner.start(1) is giving error as Failed to generate mapped ethash dataset epoch=1 err=”cannot allocate memory”

I am facing an issue here when I start the miner process with miner.start(1). It gives me error as below. I tried to search for the solution but could not find any. I am using Ubuntu 16.04 LTS on Intel i3 processor, 4 GB RAM and 4 GB Swap. I also tried to look for answers on this platform but didn't see any relevant solution.

    miner.start(1) 
    INFO [10-24|18:55:59] Updated mining threads threads=1 
    INFO [10-24|18:55:59] Transaction pool price threshold updated price=18000000000 
INFO [10-24|18:55:59] Starting mining operation null 
    INFO [10-24|18:55:59] Commit new mining work number=1 txs=1 uncles=0 elapsed=667.378µs 
    INFO [10-24|18:56:02] Generating ethash verification cache epoch=1 percentage=80 elapsed=3.010s 
    INFO [10-24|18:56:03] Generated ethash verification cache epoch=1 elapsed=3.687s 
    ERROR[10-24|18:56:03] Failed to generate mapped ethash dataset epoch=1 err=”cannot allocate memory” runtime: out of memory: cannot allocate 2164260864-byte block (119799808 in use) fatal error: out of memory