wont open

Completely ignored arguments: [--nativeLauncherVersion, 307]
[20:03:42] [Client thread/INFO]: Setting user: Grant524
[20:03:49] [Client thread/WARN]: Skipping bad option: lastServer:
[20:03:49] [Client thread/INFO]: LWJGL Version: 2.9.4
[20:03:51] [Client thread/INFO]: Reloading ResourceManager: Default
#

1. There is insufficient memory for the Java Runtime Environment to continue.
2. Native memory allocation (malloc) failed to allocate 1615536 bytes for Chunk::new
3. An error report file with more information is saved as:
4. C:\Users\Grant Summar\AppData\Roaming\.minecraft\hs_err_pid940.log
   [thread 3972 also had an error]
   #
5. Compiler replay data is saved as:
6. C:\Users\Grant Summar\AppData\Roaming\.minecraft\replay_pid940.log
   Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release