Performance
Performance and load capacity of the OS MasterMap™ Viewer is very much dependent on the amount of memory available. You can help this by increasing your swap file space, see the FAQ on how to do this. As always to free up more memory try closing other applications. The more free memory you have the more data you can view.<
As a approximate guide we've put together 2 tables identifying the max load size before your computer will start to use its swap space, resulting in a slowdown of the application. The figures are based on PC's running Microsoft operating systems.
Memory capacity for Independent Polygon GML format
| Sys Mem | Compressed (File Size / Num of Features) | Uncompressed (File Size / Num of Features) |
| 128Mb | 400Kb / 10,000 | 5.4Mb / 10,000 |
| 256Mb | 2.5Mb / 70,000 | 35.5Mb / 70,000 |
| 384Mb | 5Mb / 125,000 | 150Mb / 150,000 |
| 512Mb | 7Mb / 185,000 | 95.5Mb / 185,000 |
| 1Gb | 15Mb / 410,000 | 210Mb / 410,000 |
Memory capacity for Topological GML format
| Sys Mem | Compressed (File Size / Num of Features) | Uncompressed (File Size / Num of Features) |
| 128Mb | 330Kb / 10,000 | 6Mb / 10,000 |
| 256Mb | 2Mb / 70,000 | 38Mb / 70,000 |
| 384Mb | 4Mb / 125,000 | 70Mb / 150,000 |
| 512Mb | 5.5Mb / 185,000 | 100Mb / 185,000 |
| 1Gb | 12.5Mb / 410,000 | 225Mb / 410,000 |
