Zoran, Arnaud, I saw your posting on the ADSM-L list:
> 2) Isilon is not perfectly fitting in a big TSM environment. In order to get decent performance, a third party tool will be needed, > whose name is dsmISI. See following : http://stefanradtke.blogspot.ch/2015/06/how-to-optimize-tsm-operations-with.html > This means another layer of complexity in the setup, and another vendor to talk to, if facing performance issues. 1) dsmISI (a tool for NFS workload balancing for EMC Isilon) I 100% agree to this. dsmISI has been developed Mr. Lars Henningsen ( mailto:lars.henning...@general-storage.de) from General Storage. This is a small consulting group (only 3-4 people) based in Germany. The team has a good Spectrum Scale (TSM) Know-how no doubt and the tool is used in several customer installations, but it's a waste of money from my point of view :-( 2) How does the tool work and why is it needed? The tool does an API call to the Isilon admin interface and requests the number of currently active Isilon nodes. As each Isilon node has 2x 10 GbE network interfaces it generates on the Spectrum Scale (TSM) server twice as much NFS client mount points as there are Isilon nodes. (Info: the min number of Isilon nodes is 3 the maximum is 144.) On a fully loaded Isilon system your Spectrum Protect (TSM) server will show up to 288 NFS client mount points. BAD IDEA! The NFS code is always running as AIX/Linux kernel service. As each mount point is using Kernel Level resources (Kernel threads, mutexes and locks) it does slow down the kernel level processing and the scheduling on the system. 3) Isilon is a "lame duck" for Spectrum Scale workloads (even with dsmISI) In contrast to Dr. Stefan Radtke's BLOG entry, System Protect (TSM) is fully aware of a scalable filesystem, but Isilon does not provide the OneFS filesystem to the outside world it's only used internal to the Isilon nodes. Isilon is a scale-out NAS server but not a scale-out Filesystem! Each NFS Server to NFS Client relation is always a "1:1" relation <IP-Adress-NFS-Server-on-Isilon-Node-X> to <IP-Adress-NFS-Client-on-TSM-Server>. The dsmISI tools is trying spreading the TSM I/O load over as much NFS client mount points as possible to "parallelize" the I/O load. Still the total amount of I/O is not impressive. 4) What is best way to really solve this problem? Just using a "real" parallel filesystem on the Spectrum Scale Server is the best way to solve this problem from my point of view. Much faster, much more robust and you have only 1 mount point on the system and no need for spending money on dsmISI tools :-) More reading here, this explains the details: https://www.ibm.com/developerworks/community/blogs/storageneers/entry/Is_a_scale_out_NAS_system_the_same_as_a_scale_out_file_system?lang=en -frank- p.s. Spectrum Scale User Workshop in Germany March 2017 https://www.spectrumscale.org/spectrum-scale-user-meeting-march-89-2027-ehningen-germany/ Frank Kraemer IBM Consulting IT Specialist / Client Technical Architect Am Weiher 24, 65451 Kelsterbach mailto:kraem...@de.ibm.com voice: +49-(0)171-3043699 / +4970342741078 IBM Germany
