perfsonar development work

[Nina Jeliazkova <>]

Hi Martin, All,

Martin Swany написа:

Hi Nina,

While I can agree this is true for counters like errors/drops, for
utilization it is essential to know if the value is in bits or bytes.

I absolutely agree that it's critical from the end user's
perspective, but my (perhaps naive) point is that this
is really just a string.

Well, from service perspective it is a string. But if a client is to present the values as e.g. Mbps, then it should know how to convert the values into Mbps, that is, the string has to be interpreted by the client.

You might remember (or not), earlier versions of PerfsonarUI were ignoring the valueunit string. And everything was working fine, when one service started to report values in bits rather than presumed octets and PerfsonarUI was reporting utilization of 400%. 

Even if we consider only counters, the client should have the way of recognizing that "errors/sec" and "Eps" are the same thing, in order to plot them on the same axis, or report an average for the last hour, for example. I believe it is not correct to plot apparently different entities to the same axis or averaging between different entities.
While for the human reader the semantics of both string is obviously the same, for the client those are just strings, but DIFFERENT strings.

My point is that we need a standardized way of valueunit string interpretation, and the best thing coming to my mind is to have standardized list of units. Any other suggestions are welcome.

This is based on my desire to reduce everything to
a simple time-series regardless of whether it is a
series of active measurements, passive measurements
or the EUR/USD exchange rate.  (Actually, I'd rather not
see that last one...  :-)

Good example - EUR/USD is a standardized way of representing currency rates. I could say the same in bulgarian "евро/долар", but doubt everybody will understand it...

Best regards,
Nina

best,
martin