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On Sat, 8 Oct 2011, Brian Bockelman wrote: > > On Oct 7, 2011, at 3:37 PM, Andrew Hanushevsky wrote: >> What does that mean? You want a single entry? That's not always possible since readv allows you to read from multiple files using a single vector. > Interesting! Is there an example use of this interface? To example uses but it was put in with anticipation of some very clever person capitalizing on this feature. > Well there's a middle-ground use case here: being able to monitor > activity for each open connection. > > In our experience, without the very detailed I/O monitoring, we: > 1) Don't get any monitoring for a client that crashes (disconnects without a close). That information can be put in the summary record, if need be. I say need be because it's a relatively rare event (yes, it does happen in spurts). > 2) Don't get monitoring while a client is running. Example: it's been > 5 hours since a job has started; is this because it is getting 1 byte / > second, or because the job takes 5 hours and 1 minute? True, there is no other way of capturing this information. Another case where some more client input would make things more effecient. > So, we find it extremely useful without doing the data access patterns > use case. Either way we get the information - unrolling the vector to > include all the data, or getting a summary - we'll be happy. OK, I will take this into consideration when comming up with a fix. Andy