Performance Issues [slow/commands not working]

edit

I love sage and I think it's the best but I'm having some serious performance issues. Sometimes it takes like up to 15 seconds to compute trivial expressions. Most of the time, after some period of usage or invocation of specific commands (I haven't observed what causes this) the clear command becomes dysfunctional and I attach the logs:

    0 [main] python2.7 14516 child_info_fork::abort: address space needed by 'eclucve31.dll' (0x400000) is already occupied
---------------------------------------------
OSError     Traceback (most recent call last)
<ipython-input-50-b74f34915750> in <module>()
----> 1 get_ipython().magic(u'clear ')

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/interactiveshell.py in magic(self, arg_s)
2156         magic_name, _, magic_arg_s = arg_s.partition(' ')
2157         magic_name = magic_name.lstrip(prefilter.ESC_MAGIC)
-> 2158         return self.run_line_magic(magic_name, magic_arg_s)
2159
2160     #-------------------------------------------------------------------------

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/interactiveshell.py in run_line_magic(self, magic_name, line)
2077                 kwargs['local_ns'] = sys._getframe(stack_depth).f_locals
2078             with self.builtin_trap:
-> 2079                 result = fn(*args,**kwargs)
2080             return result
2081

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/alias.py in __call__(self, rest)
    185             cmd = '%s %s' % (cmd % tuple(args[:nargs]),' '.join(args[nargs:]))
    186
--> 187         self.shell.system(cmd)
    188
    189 #-----------------------------------------------------------------------------

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/interactiveshell.py in system_raw(self, cmd)
2245             try:
2246                 # Use env shell instead of default /bin/sh
-> 2247                 ec = subprocess.call(cmd, shell=True, executable=executable)
2248             except KeyboardInterrupt:
2249                 # intercept control-C; a long traceback is not useful here

/opt/sagemath-8.1/local/lib/python2.7/subprocess.py in call(*popenargs, **kwargs)
    166     retcode = call(["ls", "-l"])
    167     """
--> 168     return Popen(*popenargs, **kwargs).wait()
    169
    170

/opt/sagemath-8.1/local/lib/python2.7/subprocess.py in __init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags)
    388                                 p2cread, p2cwrite,
    389                                 c2pread, c2pwrite,
--> 390                                 errread, errwrite)
    391         except Exception:
    392             # Preserve original exception in case os.close raises.

/opt/sagemath-8.1/local/lib/python2.7/subprocess.py in _execute_child(self, args, executable, preexec_fn, close_fds, cwd, env, universal_newlines, startupinfo, creationflags, shell, to_close, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite)
    915                     gc.disable()
    916                     try:
--> 917                         self.pid = os.fork()
    918                     except:
    919                         if gc_was_enabled:

OSError: [Errno 11] Resource temporarily unavailable
sage: clear
    0 [main] python2.7 20456 child_info_fork::abort: address space needed by 'eclucve31.dll' (0x400000) is already occupied
---------------------------------------------
OSError     Traceback (most recent call last)
<ipython-input-51-b74f34915750> in <module>()
----> 1 get_ipython().magic(u'clear ')

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/interactiveshell.py in magic(self, arg_s)
2156         magic_name, _, magic_arg_s = arg_s.partition(' ')
2157         magic_name = magic_name.lstrip(prefilter.ESC_MAGIC)
-> 2158         return self.run_line_magic(magic_name, magic_arg_s)
2159
2160     #-------------------------------------------------------------------------

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/interactiveshell.py in run_line_magic(self, magic_name, line)
2077                 kwargs['local_ns'] = sys._getframe(stack_depth).f_locals
2078             with self.builtin_trap:
-> 2079                 result = fn(*args,**kwargs)
2080             return result
2081

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/alias.py in __call__(self, rest)
    185             cmd = '%s %s' % (cmd % tuple(args[:nargs]),' '.join(args[nargs:]))
    186
--> 187         self.shell.system(cmd)
    188
    189 #-----------------------------------------------------------------------------

/opt/sagemath-8.1/local/lib/python2.7/site-packages/IPython/core/interactiveshell.py in system_raw(self, cmd)
2245             try:
2246                 # Use env shell instead of default /bin/sh
-> 2247                 ec = subprocess.call(cmd, shell=True, executable=executable)
2248             except KeyboardInterrupt:
2249                 # intercept control-C; a long traceback is not useful here

/opt/sagemath-8.1/local/lib/python2.7/subprocess.py in call(*popenargs, **kwargs)
    166     retcode = call(["ls", "-l"])
    167     """
--> 168     return Popen(*popenargs, **kwargs).wait()
    169
    170

/opt/sagemath-8.1/local/lib/python2.7/subprocess.py in __init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags)
    388                                 p2cread, p2cwrite,
    389                                 c2pread, c2pwrite,
--> 390                                 errread, errwrite)
    391         except Exception:
    392             # Preserve original exception in case os.close raises.

/opt/sagemath-8.1/local/lib/python2.7/subprocess.py in _execute_child(self, args, executable, preexec_fn, close_fds, cwd, env, universal_newlines, startupinfo, creationflags, shell, to_close, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite)
    915                     gc.disable()
    916                     try:
--> 917                         self.pid = os.fork()
    918                     except:
    919                         if gc_was_enabled:

OSError: [Errno 11] Resource temporarily unavailable