CHECKRAM estimate if RAM will fit a new array

checks that requested memory for the new array won't exceed AVAILABLE RAM with Matlab

This script is optimistic as Matlab won't always be able to create an array using ALL available RAM, but at least you know when you certainly CAN'T create an array without digging deep into swap or worse.

function [OK,newSizeBytes,freebytes] = checkRAM(newSize, myclass)
arguments
  newSize (1,:) {mustBeNumeric}
  myclass {mustBeTextScalar}
end

% get available RAM
freebytes = stdlib.ram_free();

limit_bytes = inf; % no limit set

if ~stdlib.isoctave()
% get user set preference for memory limit
s = settings;
ws = s.matlab.desktop.workspace;

% Check if the maximum array size limit is enabled
if ws.ArraySizeLimitEnabled.ActiveValue
  limit_bytes = double(ws.ArraySizeLimit.ActiveValue) / 100 * stdlib.ram_total();
end
end

limit_bytes = min(limit_bytes, freebytes);

% variable sizing
switch(myclass)
  case 'complex single', bits = 64;
  case 'complex double', bits = 128;
  case {'single','int32','uint32'}, bits = 32;
  case {'double','int64','uint64','float'}, bits = 64;
  case {'int16','uint16'}, bits = 16;
  case {'int8','uint8'}, bits = 8;
  case {'logical','bool'}, bits = 1;
  case {'string','char'}, bits = 8;
  otherwise, error('unhandled variable class: %s', myclass)
end

newSizeBytes = prod(newSize)*bits / 8;

OK = newSizeBytes < limit_bytes;

end

%!assert(checkRAM([15,2,1], 'double'), true)

Published with MATLAB® R2024b