-Re: Understanding the min fetch rate metric
Jason Rosenberg 2013-12-26, 22:13
And, I assume the 'minFetchRate' refers to the lowest fetch rate over
all the fetchers (1 per broker) that a consumer has. I see....
On Tue, Dec 24, 2013 at 8:58 PM, Jun Rao <[EMAIL PROTECTED]> wrote:
> There is one fetcher per broker, which is responsible for fetching messages
> in all consumed topics whose leader is on that broker. We have seen a
> fetcher being killed by a bug in Kafka. Also, if the broker is slow (e.g.
> due to I/O contention), the fetch rate could also be slower than expected.
> On Tue, Dec 24, 2013 at 12:48 PM, Jason Rosenberg <[EMAIL PROTECTED]> wrote:
>> Thanks Jun,
>> I'm still not 100% clear on this. Is the min-fetch rate per topic, or
>> is it the lowest fetch rate over all topics? Or is it not topic
>> specific at all.
>> What would cause this to slow down? Or is it more a measure of the
>> consumer's rate at processing messages and ability fetching new
>> messages (regardless of topic)?
>> If we have some topics with no data at all, that match the consumer's
>> topic filter, should we expect to always see a min fetch rate of zero
>> (since at least one topic really has no messages)?
>> On Tue, Dec 24, 2013 at 1:10 PM, Jun Rao <[EMAIL PROTECTED]> wrote:
>> > I updated http://kafka.apache.org/documentation.html#monitoring
>> > Thanks,
>> > Jun
>> > On Mon, Dec 23, 2013 at 10:51 PM, Jason Rosenberg <[EMAIL PROTECTED]>
>> >> I'm realizing I'm not quite sure what the 'min fetch rate' metrics is
>> >> indicating, for consumers. Can someone offer an explanation?
>> >> Is it related to the 'max lag' metric?
>> >> Jason