Advantages :

No internal fragmentation

May save memory if segments are very small and should not be combined into one page.

Segment tables: only one entry per actual segment as opposed to one per page in VM

Average segment size >> average page size

Less overhead.

Disadvantages :

External fragmentation.

Costly memory management algorithms.

Segmentation: find free memory area big enough.

Paging: keep list of free pages, any page is ok.

Segments of unequal size not suited as well for swapping.