Hi,
On 09/08/2017 04:13 PM, Andreas Herrmann wrote:
Hi,
On 08.09.2017 15:59, Burkhard Linke wrote:
On 09/08/2017 02:12 PM, Marc Roos wrote:
Afaik ceph is is not supporting/working with bonding.
https://www.mail-archive.com/ceph-users@lists.ceph.com/msg35474.html
(thread: Maybe some tuning for bonded network adapters)
CEPH works well with LACP bonds. The problem described in that thread is the
fact that LACP is not using links in a round robin fashion, but distributes
network stream depending on a hash of certain parameters like source and
destination IP address. This is already set to layer3+4 policy by the OP.
Regarding the drops (and without any experience with neither 25GBit ethernet
nor the Arista switches):
Do you have corresponding input drops on the server's network ports?
No input drops, just output drop
Output drops on the switch are related to input drops on the server
side. If the link uses flow control and the server signals the switch
that its internal buffer are full, the switch has to drop further
packages if the port buffer is also filled. If there's no flow control,
and the network card is not able to store the packet (full buffers...),
it should be noted as overrun in the interface statistics (and if this
is not correct, please correct me, I'm not a network guy....).
Did you tune the network settings on server side for high throughput, e.g.
net.ipv4.tcp_rmem, wmem, ...?
sysctl tuning is disabled at the moment. I tried sysctl examples from
https://fatmin.com/2015/08/19/ceph-tcp-performance-tuning/. But there is still
the same amount of output drops.
And are the CPUs fast enough to handle the network traffic?
Xeon(R) CPU E5-1660 v4 @ 3.20GHz should be fast enough. But I'm unsure. It's
my first Ceph cluster.
The CPU has 6 cores, and you are driving 2x 10GBit, 2x 25 GBit, the raid
controller and 8 ssd based osds with it. You can use tools like atop or
ntop to watch certain aspects of the system during the tests (network,
cpu, disk).
Regards,
Burkhard
_______________________________________________
ceph-users mailing list
ceph-users@lists.ceph.com
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
