Striping vs Concatenation

[Ice Czar]

http://searchstorage.techtarget.com/tip/1,289483,sid5_gci1153803,00.html?track=NL-57&ad=538717

thought this might be of some interest
RAID performance at the enterprise scale
(SAN\NAS tech tips)

nice little set of questions too

# What is the nature of the I/O? (Random or sequential?)
# What is the read/write ratio? (80/20, 60/40?)
# What type of storage is being used? (Monolithic with global cache? Modular with dual controllers?)
# What type of disks are being used? (ATA, SATA, FC, solid state?)
# What size are the disks? (73 GB, 146 GB, 300 GB, larger?)
# What is the rotational speed of the disks? (5400, 10 K, 15 K?)
# How much cache is available?
# What OS? (Windows, Solaris, VMS, Tru64, HP-UX, Linux, AIX?)
# Is it a database application? (SQLserver, Oracle, DB2, Sybase, etc?)
# What is the stripe size used by the application?
# What is the stripe size used by the OS?
# What is the stripe size used by the volume manager?
# What is the chunk size used by the parity group?
# Can we match the stripe size to the chunk size?
# Which file system is being used? (RAW, UFS, QFS, NTFS, GFS, Vxfs, cluster?)
# How many drives per RAID group? (4, 8, 16?)
# What is the RAID type? (0, 1, 1+0, 0+1, 5, 5+0, 10+0)
# Software- or hardware-based RAID?
# How many spindles are available?
# How many HBA's in the server?
# How many ports on the storage array?
# How many switch hops?
# Director or edge switches? (140 port, 32 port, 64 port?)
# Is it a 1 Gb, 2 Gb, or 4 Gb fabric?
# What is the fabric design? (Core-Edge, Star, Pure Core, Meshed?)
# Who is the HBA vendor?
# What is the current queue depth being used?
# What is the best queue depth for the app?
# How many servers per storage port (Fan-in-ratio)?
# How many ISL's between switches? (Trunked?)