FSYNCS 2311 and FSYNCS 869 on the same server?!?!?

I got a new server from Hetzner with 2x SAS disks and 2x SATA disks, on Adaptec HW Raid 1.

I started by installing 2.3 version first (image from Hetzner) and run the benchmark:

pveperf
CPU BOGOMIPS: 80201.88
REGEX/SECOND: 1380442
HD SIZE: 19.84 GB (/dev/mapper/vg0-root)
BUFFERED READS: 111.62 MB/sec
AVERAGE SEEK TIME: 8.38 ms
FSYNCS/SECOND: 2311.24 :eek:
DNS EXT: 53.48 ms

I then formated the server (several times) and installed Debian 7 and Proxmox on top of it using the guide here:
http://pve.proxmox.com/wiki/Install_..._Debian_Wheezy


Since then everytime I run pveperf I am getting values similar to those:
CPU BOGOMIPS: 80198.88
REGEX/SECOND: 1264235
HD SIZE: 14.88 GB (/dev/mapper/vg0-root)
BUFFERED READS: 455.25 MB/sec
AVERAGE SEEK TIME: 3.26 ms
FSYNCS/SECOND: 869.97 :mad:
DNS EXT: 49.00 ms


Why such a difference on the same server? By the way, the server is booting from a the SAS disks, not the SATA and this is where Proxmox is installed.

Any ideas???