How to fix 'Cannot lock down 82274202 byte memory area' and 'AcquireSelfRealTime error'?

I was following the steps at https://github.com/fossasia/open-event-frontend/blob/development/docs/installation/local.md to set up the project locally. When typing ember serve, I get the following error:

Starting Ember....
Registering: list_commands
Registering: quit
Registering: toggle_erispolling
Starting Ember version 0.7.2
Initializing Ember services
Registering: loadscript
Registering: connect
Registering: meta_refresh
Registering: meta_abort
Metaserver Service created
Registering: set_value
Registering: get_value
Setting home directory to /home/rounak/.ember
Cannot lock down 82274202 byte memory area (Cannot allocate memory)
Cannot lock down 82274202 byte memory area (Cannot allocate memory)
Cannot use real-time scheduling (RR/5)(1: Operation not permitted)
JackClient::AcquireSelfRealTime error

I have already tried ways such as adding username to the audio group and modifying the limits.conf file but to no avail. I even tried sudo ember serve but then I get the following error:

Starting Ember....
Registering: list_commands
Registering: quit
Registering: toggle_erispolling
Starting Ember version 0.7.2
Initializing Ember services
Registering: loadscript
Registering: connect
Registering: meta_refresh
Registering: meta_abort
Metaserver Service created
Registering: set_value
Registering: get_value
Setting home directory to /home/rounak/.ember
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for 4294967295, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for 4294967295, skipping unlock
No protocol specified
xcb_connection_has_error() returned true
Home directory not accessible: Permission denied
No protocol specified
xcb_connection_has_error() returned true
Home directory not accessible: Permission denied
ALSA lib pcm_dmix.c:1052:(snd_pcm_dmix_open) unable to open slave
AL lib: (EE) ALCplaybackAlsa_open: Could not open playback device 'default': No such file or directory
No protocol specified
No protocol specified
No protocol specified
terminate called after throwing an instance of 'Ogre::RenderingAPIException'
  what():  OGRE EXCEPTION(3:RenderingAPIException): Couldn`t open X display :0 in GLXGLSupport::getGLDisplay at /build/ogre-1.9-Gd49ok/ogre-1.9-1.9.0+dfsg1/RenderSystems/GL/src/GLX/OgreGLXGLSupport.cpp (line 807)
Crashed with signal 6, will try to detach the input system gracefully. Please report bugs at https://bugs.launchpad.net/ember
Aborted

Please help me to overcome this.