Server load question/problem

Hi:
For the last couple of hours the server seems to be lagging. Running top shows load average at a tolerable 1-2, but idle is always at 0.0. Can anyone shed some possibilities on how idle can be stuck at 0, or anything else wrong with the picture below? Load average for this server is usually in the low 0.3 to 0.4s, FYI.
Code:
 9:18pm  up 1 day, 22:16,  1 user,  load average: 1.91, 1.71, 1.88
101 processes: 91 sleeping, 7 running, 3 zombie, 0 stopped
  9:35pm  up 1 day, 22:33,  1 user,  load average: 1.38, 1.08, 1.18
79 processes: 78 sleeping, 1 running, 0 zombie, 0 stopped
CPU states: 44.2% user, 55.7% system,  0.0% nice,  0.0% idle
Mem:   524288K av,   91060K used,  433228K free,   17332K shrd,       0K buff
Swap:  262144K av,       0K used,  262144K free                   48948K cached

  PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
14775 root      13   0  1004 1004   756 R     2.1  0.1   0:01 top
 4406 apache     1   0  9364 9364  8920 S     0.1  1.7   0:01 httpd
10638 apache    10   0  9360 9360  8916 S     0.1  1.7   0:00 httpd
13991 apache     6   0  9368 9368  8948 S     0.1  1.7   0:00 httpd
14821 apache     4   0  9348 9348  8980 S     0.1  1.7   0:00 httpd
    1 root       0   0   524  524   456 S     0.0  0.0   0:01 init
 1612 root       0   0   592  592   488 S     0.0  0.1   0:08 syslogd
 1625 root       0   0   476  476   408 S     0.0  0.0   0:00 klogd
 1662 root       0   0  2316 2316  1460 S     0.0  0.4   0:01 snmpd
 1693 named      0   0  2468 2468  1860 S     0.0  0.4   0:00 named
 1695 named      0   0  2468 2468  1860 S     0.0  0.4   0:01 named
 1697 named      0   0  2468 2468  1860 S     0.0  0.4   0:00 named
 1698 named      0   0  2468 2468  1860 S     0.0  0.4   0:00 named
 1700 named      0   0  2468 2468  1860 S     0.0  0.4   0:00 named
 1707 root       0   0  1296 1296  1160 S     0.0  0.2   0:00 sshd
 1718 root       0   0  1248 1248  1044 S     0.0  0.2   0:00 sshd
 1735 root       0   0  1004 1004   808 S     0.0  0.1   0:00 xinetd
Thanks,

 

 

 

 

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