Also set to the default, which is 1. -Jay
On Sat, Feb 8, 2014 at 1:31 PM, Sriram Subramanian < srsubraman...@linkedin.com> wrote: > What is replica.fetch.min.bytes set to? > > On 2/8/14 1:22 PM, "Jay Kreps" <jay.kr...@gmail.com> wrote: > > >Hey guys, > > > >I was running the end-to-end latency test (kafka.TestEndToEndLatency) and > >saw something a little weird. This test runs a producer and a consumer and > >sends a single message at a time and measures the round-trip time from the > >producer's send to the consumer getting the message. > > > >With replication-factor=1 I see very consistent performance with > >end-to-end > >latency at 0.4-0.5 ms which is extremely good. > > > >But with replication factor=2 I see something like this: > > > >count latency > >1000 1.9 ms > >2000 1.8 ms > >3000 1.4 ms > >4000 1.7 ms > >5000 102.6 ms > >6000 101.4 ms > >7000 102.4 ms > >8000 1.6 ms > >9000 101.5 ms > > > >This pattern is very reproducible, essentially every 4-5k messages things > >slow down to an average round trip of 100ms and then pick back up again. > > > >Note that this test is not using the new producer. > > > >Have we seen this before. The issue could be in the producer > >acknowledgement or in the highwatermark advancement or fetch request, but > >I > >notice that the default fetch max wait is 100ms which makes me think there > >is a bug in the async request handling that causes it to wait until the > >timeout. Any ideas? If not I'll file a bug... > > > >-Jay > >
