Problems with vacuum!

I'm running postgrSQL 7.2 on a linux Red Hat 8.0 box with 2GB of RAM
When I boot-up the system , this is the TOP situation:

11:59am up 4 min, 1 user, load average: 0.37, 0.26, 0.11

77 processes: 74 sleeping, 3 running, 0 zombie, 0 stopped

CPU states: 0.3% user, 0.7% system, 0.0% nice, 98.8% idle

Mem: 1031020K av, 177808K used, 853212K free, 0K shrd, 14744K buff

Swap: 2096472K av, 0K used, 2096472K free 67828K cached

After I've done a vacuum , the situation is:

12:04pm up 8 min, 1 user, load average: 0.22, 0.23, 0.12

78 processes: 76 sleeping, 2 running, 0 zombie, 0 stopped

CPU states: 2.5% user, 1.9% system, 0.0% nice, 95.4% idle

Mem: 1031020K av, 1016580K used, 14440K free, 0K shrd, 18624K buff

Swap: 2096472K av, 0K used, 2096472K free 833896K cached

As you see the memory used by vacuum isn't released anymore? Anyone know why?

My statement is: vacuumdb --analyze dbname
My pg paramaters on postgresql.conf are:

#
# Shared Memory Size
#
shared_buffers = 2048 # 2*max_connections, min 16
max_fsm_relations = 100 # min 10, fsm is free space map
max_fsm_pages = 10000 # min 1000, fsm is free space map
max_locks_per_transaction = 64 # min 10
wal_buffers = 8 # min 4

#
# Non-shared Memory Sizes
#
sort_mem = 512 # min 32
vacuum_mem = 8192 # min 1024

Did anyone know why this happend?

Distinti Saluti

Sgarbossa Domenico
X Tecnica S.R.L.
www.xtecnica.com
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