vaccumdb is giving "ERROR: out of free buffers: time to abort !"

Hai friends,
I am using postgres-7.2
System is in production state.
It has roughly 250 tables with 100 indexes.
roughly 20 tables will have 1,00,000 records each.
Lot of updations are going on.
Lot of deletions are also going on.
So have to do vacuumdb.
So Whenever i do
vaccumdb verbose analyze xyzdb
After 7 to 8 hours I am getting

ERROR:  out of free buffers: time to abort !

vacuumdb: vacuum  xyzdb failed


What to do?

Thanks in advance.

c u
raja




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Raja Kumar Thatte, Research Engineer,TMN-Group,C-DOT, 71/1, Sneha Complex, Miller Road, Bangalore-560052.

Phone:080-2389351/354, 2263399Ext362

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