rman failure ORA-04030 indicates memory issue

Rman fails with:

I notice that=20
A. A number of batch processes were added to database and likely using a good deal of "sort" area as large batch processes often do B. Volume of data added last night.
C. This error occurred along with another error:

ORA-12540: TNS:internal limit restriction exceeded

ORA-04030: out of process memory when trying to allocate 524824 bytes (pga heap,KSFQ Buffers)

I looked at TOP on Solaris while running the job that failed with ORA-04030 and out of 8 Gb, 4Gb of RAM were still showing as available.

I decreased the filesperset in rman from 10 to 4 and am concerned with the degradation of runtime for my backup processes.

The pga_aggregate_target is set at pga_aggregate_target=3D1610612736 sga_max_size=3D2147483648
processes=3D150.

I plan to look at the pga_aggregate_target related views. I also noticed in the alert.log the following:

ORA-07445: exception encountered: core dump [0000000101D51DF0] [SIGBUS] [Object
specific hardware error] [0xFFFFFFFF7CA9FE90] [] []

Along with a trace file with a specific SQL statement. =20

Question: How appropriate/inappropriate are the pga_aggregate_target, sga_max_size given 8Gb RAM and that this is the only database on the system?

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