And truthfully, for a system of this caliber, you don't really gain
anything by using XFS, certainly not from a performance standpoint.  If
you were already an XFS user on large systems and it was simply your "go
to" filesystem, then using it on this system may make sense.  And if you
don't have a working UPS, you should definitely stay away from XFS.
Power failure shouldn't cause filesystem corruption, but it may well
corrupt or zero out files that are open for write but not written.  XFS
journals metadata, not data.

i'm using xfs because i tested with ext4, xfs and reiserfs (v3) and
xfs was the fastest
i use UPS, but... well you know... some one can remove the power
cable... users sometime make mistakes :) hehe
i didn't tested the btrfs yet, i think it's not mature for production use

well power failure is a problem in any filesystem... what filesystem
you consider is the "best"?

considering that:
i'm running filesystem over md raid1
best = good power failure
files with >40gb (some mysql tables are big)
a big directory structure (root directory with man pages libs, linux
kernel and some packages that i compile (php, mariadb, apache), and
others linux tools, etc...)
a home directory with maybe many temporary files, mysql sometime
create temporary files for query sorting, in this case crud operations
happens very often, create file/put data/read/delete file

well i think it's a test scenario, but experiences/ideas are wellcome

-- 
Roberto Spadim