Hi Tore, An answer from the dark side. I am not aware of the current situation, but I used to do this more than 5 years ago (no z now). I spent quite some time with Rob vd Heij on analyzing our TSM setup. The major conclusion is that there was far too much overhead (mainly due to buffer massaging by QEBS/SEBS) on the vswitch path to get to any meaningfull speed. It just burned up the IFL's. We ended up dedicating several 1GB OSA's in a load balanced config. That got us to about 300MB/s in a z9BC with acceptable overhead.
Best regards Pieter Harder Brabantwater -----Oorspronkelijk bericht----- Van: Linux on 390 Port [mailto:[email protected]] Namens Agblad Tore Verzonden: vrijdag 15 januari 2016 11:34 Aan: [email protected] Onderwerp: Max NFS speed via vswitch and 10GBit adapter ? Hi, we are trying to bump up the speed doing file transfers via a vswitch connected to a 10Gbit OSA. There seems to be a lot of parameters having a significant impact on speed here. It's for getting best speed for a TSM Server backing up its own db2 database That lives on std eckd disk onto nfs mounted disks. Nfs mounts in fstab: 172.19.27.227:/tsmgot90_isfs_1000_q1000n /tsmgot90/stg/1 nfs vers=3,tcp,hard,intr,rsize=131072,wsize=131072,bg 0 0 z/VM Version 6 Release 3.0, Service Level 1502 (64-bit) RHEL Santiago 6.7 So far we have using a dd command got 158 MB/s: root@zlintcp2:/etc/modprobe.d# time dd if=/dev/zero of=/tsmgot90/stg/2/testfile bs=256K count=10100 10100+0 records in 10100+0 records out 2647654400 bytes (2.6 GB) copied, 16.7146 s, 158 MB/s real 0m17.410s user 0m0.003s sys 0m2.231s nfsiostat indicates to much cpu is used, not sure if it is true values. We would like to reach at least 200MB/s, preferably 300MB/s Anyone having experiences or hints and tips ? What is the actual limit here ? BR /Tore ________________________________________________ Tore Agblad zOpen, IT Services Volvo Group Headquarters Corporate Process & IT SE-405 08, Gothenburg Sweden E-mail: [email protected] http://www.volvo.com/volvoit/global/en-gb/
