Admin UI - Memory Graph on Dashboard shows NaN for unused Swap

If the System doesn't use Swap, the displayed memory graph on the dashboard shows NaN (not a number) because it tries to divide by zero.
admin url : solr/collection/admin/system?wt=json&&indent=true

"system":{
"name":"Linux",
"version":"3.13.0-48-generic",
"arch":"amd64",
"systemLoadAverage":0.0,
"committedVirtualMemorySize":27111653376,
"freePhysicalMemorySize":48219590656,
"freeSwapSpaceSize":0,
"processCpuTime":67938650000000,
"totalPhysicalMemorySize":67548606464,
"totalSwapSpaceSize":0,
"openFileDescriptorCount":213,
"maxFileDescriptorCount":4096,
"uname":"Linux ip-172-22-65-57 3.13.0-48-generic #80-Ubuntu SMP Thu Mar 12 11:16:15 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux\n",
"uptime":" 06:33:04 up 57 days, 20:20, 0 users, load average: 0.00, 0.01, 0.05\n"}}