Optimal File System config for 2.5TB RAID5

[Danny Do]

Hello,

I am building a 6x500GB SATA HARDWARE RAID5 storage server to
- Store large files, 10BM~1GB/file
- Handling 500+ concurrent connections
- Transfer rate around 100~200Mbit/s

I am thinking of using the patch from Wojciech Puchar to reduce hard drive
data seek in order to handle large number of concurrent connections whilst
outputting 100~200Mbit/s.

patch /usr/src/sys/sys/param.h
#ifndef DFLTPHYS
#define DFLTPHYS        (1024 * 1024)   /* default max raw I/O transfer size
*/
#endif
#ifndef MAXPHYS
#define MAXPHYS         (1024 * 1024)   /* max raw I/O transfer size */
#endif
#ifndef MAXDUMPPGS


To store files greater than 10MB, I come up with the following proposal for
my File System:
- UFS2
- Soft Update  Enable
- block-size   1,048,576

I am not completely sure what advantage I got from this configuration but I
am pretty sure that FSCK is much quicker with 1M file system block-size. 

Is there any other thing I need to consider in term of performance and
reliability?

I hope that this system will perform much better than my current 6x300GB
SCSI 10K RPM system.

Appreciate any advice,

Danny