perfSONAR User Q&A and Other Discussion

["Christopher J. Tengi" <>]

Greetings,
        We have been running a few toolkit hosts and a measurement archive 
for a few months now, and plan to scale things *way* up in the 
not-too-distant future.  I have the MA on a fairly hefty Dell server, and 
would like to move it to a VM - it does no measurements of its own.  The 
hardware that the MA currently lives on has 2, 8 core CPUs (2.4 GHz), 24 GB 
of RAM, and around 7 TB of disk.  Kind of overkill for what we’re doing, but 
what I had not in use at the time.  :-)

        I’m looking for a more realistic configuration on a VM for a system 
that will act as the MA for around 200 (eventually) low-cost mesh nodes at 
building entry points, as well as a few higher-performance hosts in the data 
centers and on the Science DMZ, once we deploy one.  The VM would also be 
running MaDDash for the on-campus mesh as well as one or two (or 3) wide-area 
meshes.  Note that the members of the wide-are meshes would be using their 
own MA, rather than this VM.  Based on what I’ve read so far, I’m assuming 
that 4 cores and 8 GB of RAM would be more than sufficient for these 
purposes, but I’m not sure about the disk requirements.

        The Toolkit documentation talks about 100 GB of disk space, with the 
assumption that old data is not automatically cleaned from the local MA.  If 
I had a 200 node on-campus mesh doing latency (10pps) and bandwidth 
measurements (20s every 2h), is there a rule of thumb I could use to 
determine how much disk to put on the MA if I wanted to keep the data for a 
year?  Six months? Three months?  As for the CPU and RAM, if I’ve drastically 
over-specified or under-specified, I’d like to know.  What has your 
experience shown?

                Thanks,
                        /Chris