ClassCastException when including all metrics via domain_regex

[KoenDG]

There's no way to fully add the relevant info here without either removing too much, or revealing setup details. So here's my description:

I've run into a situation where I'm trying to get all JMX metrics from a Solr database.

Solr has what's known as a FieldCache. One of the beans for this is the total_size of the FieldCache.

In my logs I'm seeing this(manually truncated here):

Error while trying to match attributeInfo configuration with the Attribute: <truncated>category=CACHE,scope=core,name=fieldCache : javax.management.MBeanAttributeInfo[description=null, name=total_size, type=java.lang.String, read-only, descriptor={}]
java.lang.ClassCastException
Unable to get metrics from <truncated>category=CACHE,scope=core,name=fieldCache - total_size: java.lang.NumberFormatException: For input string: "232.2 MB"

Looks like the output is "232.2 MB" and an attempt is made to cast this to a number. And it fails there.

What steps can I take to resolve this? Or is this something in the code that needs to be resolved?

Since I want to get all possible metrics from the database, I'm using a domain_regex instead of mapping individual metrics. Should I move to mapping individual metrics in the configuration? Or would that still not work?

[KoenDG]

Looking further at the documentation... it seems like this is just straight up not possible.

Is there a way to say in the configuration, for a specific bean: must be interpreted as a specific dataype?

[carlosroman]

It looks like the problem here is Solr is returning total_size as human readable String rather than just the number of bytes. Looking through the Solr code not sure if there is a way to stop Solr making it human readable or if there is a way to get size or ramBytesUsed from the MBean. It should be possible as suggested by the docs here.

[KoenDG]

I'll give it an attempt, though from what I'm reading those statistics are only for the QueryResultCache, whereas I'm explicitely only in interested in the FieldCache

[KoenDG]

Yeah no those values are not the same thing. It seems total_size is the only output given for FieldCache and that's always going to be a string like "405 MB".

And from what I can tell there is currently no way of dealing with that?

[carlosroman]

Yes, at the moment there is no way to deal with values such as 405 MB. Having looked at how that value is created I'm not sure what our config would look like for such a value. We also wouldn't want to do this for every string that fails to be converted to a number.
This is pretty much the same as requested in #372

[KoenDG]

Oh wow, I did a bit of a search before making this, but I don't recall finding that.

Yes, that seems identical, so I'll close this one.

Thanks for your time.