[squid-users] big difference between "Current Size" and "Filesystem Space in use" ?!

I am seeing huge difference between current size of the cache and
filesystem space in use in cachemgr output. I dont have anything else
using that disk! Why is this happening? Almost 3gbyte difference!?

I use FreeBSD 4.7-stable and squid squid-2.4-200209132300 snaphost
configured with these options
./configure --enable-err-language=Turkish --enable-truncate
--disable-unlinkd --enable-removal-policies=heap --enable-underscores
--enable-storeio=diskd

Is this a known problem? what can be the cause?

Store Directory #0 (diskd): /usr/local/squid/cache/disk1
FS Block Size 2048 Bytes
First level subdirectories: 16
Second level subdirectories: 256
Maximum Size: 7168000 KB
Current Size: 4895780 KB
Percent Used: 68.30%
Filemap bits in use: 376431 of 524288 (72%)
Filesystem Space in use: 7633916/8745126 KB (87%)
Filesystem Inodes in use: 647231/1097598 (59%)
Flags:
Pending operations: 0

Store Directory #1 (diskd): /usr/local/squid/cache/disk2
FS Block Size 2048 Bytes
First level subdirectories: 16
Second level subdirectories: 256
Maximum Size: 7168000 KB
Current Size: 4896864 KB
Percent Used: 68.32%
Filemap bits in use: 346566 of 524288 (66%)
Filesystem Space in use: 7824110/8745126 KB (89%)
Filesystem Inodes in use: 605569/1097598 (55%)
Flags:
Pending operations: 0

Store Directory #2 (diskd): /usr/local/squid/cache/disk3
FS Block Size 2048 Bytes
First level subdirectories: 64
Second level subdirectories: 256
Maximum Size: 34816000 KB
Current Size: 32059650 KB
Percent Used: 92.08%
Filemap bits in use: 3172307 of 4194304 (76%)
Filesystem Space in use: 33514708/39576738 KB (85%)
Filesystem Inodes in use: 3722093/4950398 (75%)
Flags: SELECTED
Pending operations: 0
Received on Tue Nov 12 2002 - 12:24:26 MST