artifactory 2.0.6 speed problems after upgrade

I upgraded from artifactory v1.2.5-rc5 to 2.0.6 recently by exporting the original system (using artadmin) then re-importing.  Since then we have seen periods when the response from artifactory is extremely slow to respond to requests, though it eventually does work.

There's very little in the artifactory log files - no errors and nothing unusual.  top indicates that there is a significant bottle neck somewhere because when artifactory is slow it show wait states in the >50% range.

the server in use is the same as the one that the previous version was on, so I am thinking that there is soemthing about the new version of artifactory, perhaps memory usage, that is causing this.  However, top indicates that artifactory is using about 15% of the 4GB available on the machine, so it's not using an excessive amount.

Does this new version  (2.0.6) require or use more memory than 1.2.5rc5 by default?

Thanks
Damon