Someone posted the same problem on this forum regarding this issue that :
Right now the blog is shown in its entirety. So if you have a 100 entries with pictures and other data, all that data is loaded on one page thus making the page load times take forever. We need to be able to control the amount of posts that are shown at one time to increase load times and then allow the user to look in the archives. So basically, for example, the blog.aspx page would show the 10 most recent entries on page 1 and the 10 more on page 2, so forth and so on.