Compression ratio better with level 1 than with any other level

```
1#hdd-0.pvhd : 1179648 -> 128020 (x9.215), 543.1 MB/s, 1139.9 MB/s, 10 ms, 5 ms
2#hdd-0.pvhd : 1179648 -> 128579 (x9.174), 482.0 MB/s, 1197.9 MB/s
3#hdd-0.pvhd : 1179648 -> 160125 (x7.367), 240.1 MB/s, 1133.0 MB/s
4#hdd-0.pvhd : 1179648 -> 160113 (x7.368), 289.7 MB/s, 1144.3 MB/s
5#hdd-0.pvhd : 1179648 -> 162367 (x7.265), 140.7 MB/s, 1120.8 MB/s
6#hdd-0.pvhd : 1179648 -> 143708 (x8.209), 109.8 MB/s, 1130.7 MB/s
7#hdd-0.pvhd : 1179648 -> 144305 (x8.175), 83.0 MB/s, 1129.4 MB/s
8#hdd-0.pvhd : 1179648 -> 136609 (x8.635), 66.3 MB/s, 1170.4 MB/s
9#hdd-0.pvhd : 1179648 -> 136610 (x8.635), 57.7 MB/s, 1220.6 MB/s
10#hdd-0.pvhd : 1179648 -> 137487 (x8.580), 36.6 MB/s, 1268.4 MB/s
11#hdd-0.pvhd : 1179648 -> 139949 (x8.429), 29.2 MB/s, 1359.7 MB/s
12#hdd-0.pvhd : 1179648 -> 139949 (x8.429), 29.6 MB/s, 1351.3 MB/s
13#hdd-0.pvhd : 1179648 -> 142723 (x8.265), 28.3 MB/s, 1690.0 MB/s
14#hdd-0.pvhd : 1179648 -> 141124 (x8.359), 26.5 MB/s, 1658.9 MB/s
15#hdd-0.pvhd : 1179648 -> 141102 (x8.360), 22.9 MB/s, 1743.0 MB/s
16#hdd-0.pvhd : 1179648 -> 134562 (x8.767), 6.32 MB/s, 1225.1 MB/s
17#hdd-0.pvhd : 1179648 -> 134558 (x8.767), 5.98 MB/s, 1222.6 MB/s
18#hdd-0.pvhd : 1179648 -> 133269 (x8.852), 4.69 MB/s, 1087.5 MB/s
19#hdd-0.pvhd : 1179648 -> 133176 (x8.858), 4.29 MB/s, 1106.4 MB/s
20#hdd-0.pvhd : 1179648 -> 133176 (x8.858), 4.34 MB/s, 1069.8 MB/s
21#hdd-0.pvhd : 1179648 -> 133150 (x8.860), 4.24 MB/s, 1105.0 MB/s
22#hdd-0.pvhd : 1179648 -> 133121 (x8.861), 4.26 MB/s, 1120.0 MB/s
```
http://users.beotel.net/~gwh/zstd/zstd2.zip

One more thing: could you add the **actual time**, in mili seconds, like I added in the first line?