Quad Xeon Processor server slow


Active Member
Mar 10, 2010
Sydney Australia
I just picked up a refurbished DELL RACK MOUNT POWEREDGE R820 4 X XEON - E5-4607 2200 192GB Ram.
Latest Proxmox installed and updated. (5.4)
8 x 3TB 2.5" HDD Raid Z2 zfs.GUI shows total 48 cores.
Doing some testing, installed Windows 10 pro and Windows 7 Pro.
Both are running like "dogs".
To make them usable I have had to run each with 16 cores and 36GB ram.
To restore a 90GB backup (200GB VM), it took 133 minutes
On a dell R710 Dual processor same restore takes 26 min.
Any suggestions ???
depending on the workload, raidz2 is not very good for io (especially with slow spinners)
i would suggest to instead do raid10 on that, but spinning disks are never very fast
Hi Dominik
Thanks for the prompt reply,
The dell R710, has same drives and and also same raid config.
Yet it is 5 times faster than the R820

is there a raid controller on the r820?
The Dell poweredge R820 is a Sandy bridge generation product. This generation of processors only have 2 QPI transports which means that in a 4 socket arrangement SOME chip-to-chip IO will have to go through two hops. When this happens the cost in latency is atrocious, and to get good i/o out of these systems you have to be VERY deliberate in your NUMA allocations, AND be very cognizant which slot controls your disk interfaces (PCI slots are pinned to a specific cpu socket.)

This may be an instructive experiment for you- remove two cpu's out. you'll need to remove/reposition the memory associated with them, and possibly have to move cards- and see what it does to your performance :)


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