Lag is server-wide most of the time. Believe me, blocks not breaking in skyblock and dropping but then disappearing and replacing itself is annoying. As well as "lag" happening then 3 people say lag again in spleef...
the hole sky blocks server said the same thing and i wouldnt lagg on my own i got 32 gigabits of ram a nd a nice grafics card
First off, it's Gigabytes. Gigabits is a measurement of network speed, and is one-eighth of a gigabyte. --TECHNICAL RANT OVER-- Lag is not a "bug". Lag can not be fixed by changing code. Therefore, unfortunately, the best that we can suggest for you is for you to either: 1) Try playing on the server at a different time, when there's less people online. or 2) Deal with the lag.
It's seems to be a common misconception in the Minecraft community that more RAM = less lag. We have plenty of RAM, upgrading won't make a single difference.