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Created 12-18-2015 03:55 AM
Where can I see the overall peak memory usage of a query. In the textplan I get an estimated per-host requirement. But we want to compare RDF queries with up to 200 joins for memory efficiency and need the real per-host peak memory usage. Where can I find it?
Created 12-18-2015 09:16 AM
You can find that information in the runtime profile. There are various ways to get it - e.g. from impala-shell you can run profile; after the query. The PerHostPeakMemUsage counter will tell you the peak memory usage for each impala instance executing the query. I think getting the numbers for each host and summing them gives you roughly what you want.
200 joins sounds like an interesting query - let us know how it goes.
Created 12-18-2015 09:17 AM
I misread your question and didn't realise you wanted the per-host peak, PerHostPeakMemUsage gives you exactly what you want.
Created 12-18-2015 09:16 AM
You can find that information in the runtime profile. There are various ways to get it - e.g. from impala-shell you can run profile; after the query. The PerHostPeakMemUsage counter will tell you the peak memory usage for each impala instance executing the query. I think getting the numbers for each host and summing them gives you roughly what you want.
200 joins sounds like an interesting query - let us know how it goes.
Created 12-18-2015 09:17 AM
I misread your question and didn't realise you wanted the per-host peak, PerHostPeakMemUsage gives you exactly what you want.