comfused about /proc/meminfo

[George Thompson]

RHEL4

sar is showing 99% memory used. The apps seem to be only consumint half of
the 8G memory.
The /proc/meminfo file shows a very high value for the "Mapped" value .
.This seems to e nearly half of the 8G Memory . Is this normal ??

cat /proc/meminfo
MemTotal:      8164748 kB
MemFree:        351040 kB
Buffers:         71476 kB
Cached:         200920 kB
SwapCached:      37684 kB
Active:        3758864 kB
Inactive:       165624 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:      8164748 kB
LowFree:        351040 kB
SwapTotal:    16779884 kB
SwapFree:     16643608 kB
Dirty:            2384 kB
Writeback:           0 kB
Mapped:        3670064 kB
Slab:           173056 kB
CommitLimit:  20862256 kB
Committed_AS:  7815400 kB
PageTables:      13932 kB
VmallocTotal: 536870911 kB
VmallocUsed:    271300 kB
VmallocChunk: 536599035 kB
HugePages_Total:     0
HugePages_Free:      0
Hugepagesize:     2048 kB

G