Logging free bytes on disk seems useful

src/main.cpp

@@ -6004,6 +6004,7 @@ bool CheckDiskSpace(uint64_t nAdditionalBytes)
 {
     uint64_t nFreeBytesAvailable = boost::filesystem::space(GetDataDir()).available;
 
+    fprintf(stderr,"Free bytes on disk: %d\n", nFreeBytesAvailable);
     // Check for nMinDiskSpace bytes (currently 50MB)
     if (nFreeBytesAvailable < nMinDiskSpace + nAdditionalBytes)
         return AbortNode("Disk space is low!", _("Error: Disk space is low!"));