Which version do you use v2.1 or v2.1.1?
We have the same problem whith our GF v2.1 cluster and I believe/hope that this is a known bug which is fixed with patch 2 for GF v2.1, see
http://blogs.sun.com/GlassFishForBusiness/entry/sjs_as_9_1_u25
entry "[6774854] AS9.1 very, very slow to sychronize an 80Mb application via node agent, with `cluster' profile".
This patch is only available to customers with subscription however I assume that it is also included in v2.1.1.
If you are using v2.1 and upgrading to 2.1.1 fixes the problem I would be very interested.
Niklas.
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