Hi Taylor,
This is an FAQ, that was asked some time ago as well:
http://mail-archives.apache.org/mod_mbox/incubator-kafka-users/201108.mbox/%3ccafbh0q3qgsyxn4kjtth0zz9djz7j14tm5g24rfjsihffbqd...@mail.gmail.com%3E
GetOffsetShell doesn't return the offset of every message. It returns the
offset of the first message in every segment file. If you provide a time,
the offsets you get back are based on the last modified time of the segment
files.
It may be a good idea to paraphrase the above to be displayed with the
tool's help message.
Thanks,
Joel
On Wed, Sep 21, 2011 at 4:18 PM, Taylor Gautier <tgaut...@tagged.com> wrote:
> Hi,
>
> Using Kafka 0.6.
>
> I'm trying to use get offsets but it doesn't seem to work as I expect. I
> have a test topic that has some messages in it. Here's the output of a
> test client that starts from offset 0 and prints all messages/offsets for
> the topic:
>
> Consumed message:foo offset: 12
> Consumed message:bar offset: 24
> Consumed message:foo offset: 36
> Consumed message:bar offset: 48
> Consumed message:hello offset: 62
> Consumed message:world offset: 76
>
> Here's a class to print the last n offsets:
>
> public class SimpleConsumerDemo
>
> {
>
> public static void main(String[] args)
>
> {
>
> SimpleConsumer simpleConsumer = new SimpleConsumer("localhost", 9092,
> 1000, 1024);
>
>
> long[] offsets = simpleConsumer.getOffsetsBefore("test", 0, -1L, 1);
>
> for (long l : offsets) {
>
> System.out.println("offset: " + l);
>
> }
>
> }
>
> }
>
>
> Running this as above, with 1 offset, yields expected results:
>
> ----output-----
>
> offset: 76
>
>
> However, asking for 3 offsets yields unexpected results:
>
>
> change to: long[] offsets = simpleConsumer.getOffsetsBefore("test", 0, -1L,
> 3);
>
> ----output-----
>
> offset: 76
>
> offset: 0
>
>
> I expected:
>
>
> ----output-----
>
> offset: 76
>
> offset: 62
>
> offset: 48
>
> Any idea why I did not get what I was looking for/what I am doing wrong?
>
