I am using Oracle 10.2.0.2 with RAC (6 nodes ) + ASM on RHEL 3. I use LMT bigfile tablespaces and ASSM. I am aware of the exchange partition bug, but my case looks different: I don't seem to have any deadlocks and using the workaround you mention (fixed quotas) did not help.
If you preallocate the storage, you'll avoid the updates on tsq$.
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