Big Filesystem and Compressed Filesystem?

[Ben Russo]

(see below for long story background )

The last time I created a large HW RAID5 volume (1.6 TB) the kernel was 
unable to see all of it... If I create several smaller block devices 
(like 400GB each) can LVM bind them together into a larger single 
filesystem?  ( I am aiming for 4-6 TB )

Is there anyway to greate a BIG robust random rw access filesystem that 
is transparently compressed and supports large files (up to several 
gigabytes each? )

I have seen cramfs and squashfs  both of which have sub 2GB filesize 
limit problems and read/write random access issues.  So they don't fit 
my needs.  Please don't respond saying "just gzip each file" duh... I 
already thought of that.

Background info:.....................................
       My employer has large amounts (10GB/day) of telecommunications
       related billing data  that in it's raw form is BIG (1-2GB ea) 
flat
       ascii text files with fixed record formats with carriage returns.
       We do tape
       backups every night (incrementals) and we have weekly full backups
       that go offsite.  We currently keep 3 months of data online and
       this is fine for any urgent issues.
        Unfortunately every few months a customer (or the IRS or a local
       tax agency ) will
       challenge some accounting information and we have to dig up
       several months of data from tape.  This is very time consuming.
       The raw billing data will *always* continue to be backed up to
       tape and sent offsite.  However because it is such a resource
       drain to restore old tapes from offsite archives I have asked if
       we could keep an "online" archive locally.  The answer of course 

       is yes, but only if it is CHEAP.  This raw billing data 
compresses
       at a rate of 20:1 or 30:1 is just fixed records, most of which is
       just ascii spaces or ascii 0-9.  So if I could find a compressed
       filesystem solution that would handle this it would be great, I
       could get an IDE or SATA disk array with hardware RAID 5 and have
       a huge (4 or 6 TB ) filesystem and with transparent compressed 

       filesystem (even if it was only 5:1) that would be enough for
       several years worth of data.  Even if it is very slow disk I/O, it
       would still be faster than offsite tape. And it would be immensely
       easier!
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