V-Sync Uses Excessive Percentage

When v-sync is turned on, frame rate is synced, as intended, but in the F3 menu pie chart, the "unspecified" section becomes unusually large, taking over 50% of the chart. This also has the effect of "stealing" space from the game-renderer especially, causing lag, especially during chunk loading.

Screenshots were taken when all chunks were loaded on render distance 16 (zero chunk updates)