"I don't believe that is true. If you ask them then sure, they will pick reliability but in actual operations they will performance first most of the time."
No, they would not. None have any complaints about our filesystem performance, either on my CentOS 4 machines using Ext3 mounted data=ordered, or on my later servers with Ext4 mounted nodelalloc. Benchmarking of Ext4 with and without nodelalloc always come out pretty much a wash. I've never understood what the fuss was about. Delayed allocation just doesn't improve performance noticeably. Nor did Ext3 with data=ordered in any of the server scenarios I have been involved with. And I see no appreciable difference regarding fragmentation rates, either.
If you've done your own benchmarks with your own server workloads which disagree with mine, I would be interested in hearing about them.
But regarding delayed allocation in ext4 and xfs, and the "wonders" of making data=writeback the default for ext3, I must observe that the Emperor has no clothes.