Did a freeze-up occur in there someplace? Otherwise, that is not not so useful.
You should try to decrease the sar interval to 1 min if you can. The extra overhead is negligible and the extra information can be very valuable. I'd also have something like "vmstat 5" running and capture that. Although perhaps one of the options to sar other than -u capture that same information, I know little of the other sar options.