Iperf gives about 7Gb/s between a radosgw host and one of my OSD hosts (8
disks, 8 OSD daemons, one of 3 OSD hosts). When I benchmark radosgw with
cosbench I see high TCP retransmission rates (from sar -n ETCP 1). I don't
see this with iperf. Why would Ceph, but not iperf, cause high TCP
retran
On 04/15/2018 08:18 PM, Robert Stanford wrote:
Iperf gives about 7Gb/s between a radosgw host and one of my OSD
hosts (8 disks, 8 OSD daemons, one of 3 OSD hosts). When I benchmark
radosgw with cosbench I see high TCP retransmission rates (from sar -n
ETCP 1). I don't see this with iperf.
I should have been more clear. The TCP retransmissions are on the OSD
host.
On Sun, Apr 15, 2018 at 1:48 PM, Paweł Sadowski wrote:
> On 04/15/2018 08:18 PM, Robert Stanford wrote:
>
>>
>> Iperf gives about 7Gb/s between a radosgw host and one of my OSD hosts
>> (8 disks, 8 OSD daemons, one of
Those retransmission happen at the TCP handshake or after that? Did you
checked error counters on your NICs? Maybe your radosgw is sending too
much requests to OSDs.
On 04/15/2018 10:54 PM, Robert Stanford wrote:
>
> I should have been more clear. The TCP retransmissions are on the
> OSD host.