Having recently completed the second book of Malory's Arthurian epic, I can say this: so. damn. dense!
Now, I say dense in a good way, as in 'there is a hell of a lot of content happening in a very small space'. Seriously, one could easily make a whole trilogy of films out of this one book; you have Arthur's fight with the dozen kings, a jousting scene, various prophecies by Merlin, the renegade knight murdering people, the killing of that knight, and Balan and Balin fighting. This is alongside the numerous asides offered by the narrator on the future of each event. All in all, you can't read a page without thinking to yourself how much is unfolding and how much time is elapsing in each book.
In a sense, then, Malory reminds me of John Milton, at least in how he sneakily packs in time, folding temporal loops in crevices and whatnot. Malory, like Milton in the opening invocation to Paradise Lost, covers a lot of ground in a short period; at one moment the reader is in the present, then fast forward to a couple of weeks in the future, back to some other character's present (before the two weeks), then back to the immediate future. Expect a few allusions to what will happen in the far future before coming back down to the present, and throw in a few nods to the past, and you have a convoluted artifact at least as far as time is concerned.
Since Malory is borrowing from so many traditions and making the assorted Arthurian tales into a single narrative, this is to be expected. I would have been more surprised if the temporalis was straightforward. Though I do not find this to be a bad distraction from the text, it is something I notice and causes me to remain on my toes as I push deeper into the narrative. But many people, I feel, would have a fit with how time is handled. So, if you dig into this text, be prepared.