vacuumdb -z do a reindex?

I thought 'vacuumdb -z dbname' also reindex is this true?

I've had a simple update running for over 4 hours now (see results from
pg_top below). The sql is:

The database has 1016789 records, vacuumdb -z is ran once a day. I have
not ran 'reindexdb' in weeks. The system is a:

2xIntel 4-core Xeon Model E5430 (Harpertown) 2.66GHz, 32GB RAM and
8x145GB SAS drives configured with software RAID10

Your comments are appreciated.
--irene

>> last pid:  1185;  load avg:  2.17,  2.21,  1.60;       up 38+01:36:40
                 13:52:27 
>> 14 processes: 2 running, 12 sleeping
>> CPU states: 14.0% user,  0.0% nice, 10.5% system, 75.4% idle,  0.0% iowait
>> Memory: 11G used, 20G free, 456M buffers, 8724M cached
>> Swap:
>>
>>   PID USERNAME PRI NICE  SIZE   RES STATE   TIME   WCPU    CPU COMMAND
>> 28508 postgres  17    0   93M   38M run   265:53 58.42% 99.08% postgres: postgres metadata 140.252.26.34(34717)
UPDATE
>> 31609 postgres  16    0   91M   36M run     7:05 57.85% 98.09% postgres: system_admin metadata 140.252.26.34(43303)
SELECT
>> 25156 postgres  16    0  102M   46M sleep   7:28  0.00%  0.00% postgres: system_admin metadata 140.252.6.51(40350)
idle
>> 25363 postgres  18    0   93M   37M sleep   5:08  0.00%  0.00% postgres: system_admin metadata 140.252.6.51(35951)
idle
>> 31622 postgres  15    0   95M   38M sleep   1:45  0.00%  0.00% postgres: system_admin metadata 140.252.6.51(51917)
idle
>> 31624 postgres  15    0   95M   38M sleep   0:14  0.00%  0.00% postgres: system_admin metadata 140.252.6.51(53908)
idle
>> 28755 postgres  15    0   91M   10M sleep   0:02  0.00%  0.00% postgres: postgres keyword 140.252.26.33(41270) idle
>> 28757 postgres  15    0   91M   10M sleep   0:02  0.00%  0.00% postgres: postgres keyword 140.252.26.33(41272) idle
>> 28756 postgres  15    0   91M   10M sleep   0:02  0.00%  0.00% postgres: postgres keyword 140.252.26.33(41271) idle
>> 28758 postgres  15    0   91M   10M sleep   0:02  0.00%  0.00% postgres: postgres keyword 140.252.26.33(41273) idle
>> 28754 postgres  15    0   92M 9724K sleep   0:02  0.00%  0.00% postgres: postgres keyword 140.252.26.33(41269) idle
>> 25180 postgres  15    0   91M 7016K sleep   0:00  0.00%  0.00% postgres: postgres metadata 140.252.6.51(33997) idle
>> 25179 postgres  15    0   91M 6956K sleep   0:00  0.00%  0.00% postgres: postgres metadata 140.252.6.51(47331) idle
>>  1186 postgres  16    0   90M 4808K sleep   0:00  0.00%  0.00% postgres: arcsoft metadata [local] idle
>> [arcsoft@archdbn1 ~]$ date
>> Fri Nov 27 13:53:28 MST 2009

--
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Irene Barg                    Email:  ibarg@noao.edu
NOAO/AURA Inc.                 http://www.noao.edu/noao/staff/ibarg
950 N. Cherry Ave.            Voice:  520-318-8273
Tucson, AZ  85726 USA           FAX:  520-318-8360
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