Hi all, The recently introduced IOMonitor allows the FileStore to trigger I/O events. Callback methods from IOMonitor can be implemented to receive information about segment reads and writes.
A trivial implementation of IOMonitor is able to track the following raw data. - The number of segments read and write operations. - The duration in nanoseconds of every read and write. - The number of bytes read or written by each operation. We are about to expose this kind of information from an MBean - for the sake of discussion, let's call it IOMonitorMBean. I'm currently in favour of starting small and exposing the following statistics: - The duration of the latest write (long). - The duration of the latest read (long). - The number of write operations (long). - The number of read operations (long). I would like your opinion about what's the most useful way to present this data through an MBean. Should just raw data be exposed? Is it appropriate for IOMonitorMBean to perform some kind of aggregation, like sum and average? Should richer data be returned from the MBean, like tabular data? Please keep in mind that this data is supposed to be consumed by a monitoring solution, and not a by human reader.
