Massive number of rows in wp_postmeta

We have a relatively large site using Course press pro. Its slow. but we're moving it to a new server. I noticed the size of the wp_postmeta table is huge. 1.6 million rows.
Is this ok? Is this acceptable or is something wrong here?

mysql> select count(*) from wp_postmeta;
+----------+
| count(*) |
+----------+
| 1609533 |
+----------+