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Guozhang Wang commented on KAFKA-2607: -------------------------------------- Thanks for sharing Ismael. This is a great read. I vaguely remember in J7 the perf difference of nanoTime is indeed non-negligible, but I cannot find the source of my memory now... > Review `Time` interface and its usage > ------------------------------------- > > Key: KAFKA-2607 > URL: https://issues.apache.org/jira/browse/KAFKA-2607 > Project: Kafka > Issue Type: Improvement > Affects Versions: 0.11.0.0, 1.0.0 > Reporter: Ismael Juma > Priority: Major > Labels: newbie > > Two of `Time` interface's methods are `milliseconds` and `nanoseconds` which > are implemented in `SystemTime` as follows: > {code} > @Override > public long milliseconds() { > return System.currentTimeMillis(); > } > @Override > public long nanoseconds() { > return System.nanoTime(); > } > {code} > The issue with this interface is that it makes it seem that the difference is > about the unit (`ms` versus `ns`) whereas it's much more than that: > https://blogs.oracle.com/dholmes/entry/inside_the_hotspot_vm_clocks > We should probably change the names of the methods and review our usage to > see if we're using the right one in the various places. -- This message was sent by Atlassian JIRA (v7.6.3#76005)