Strange limit behavior

[morigs]

Requirement - what kind of business use case are you trying to solve?

Searching traces by tags. View a certain amount of recent traces.

Problem - what in Jaeger blocks you from solving the requirement?

Jaeger shows very different search results depending on the limit. Some of traces from begging and the middle of the full list disappears on small limits.

In addition, the number of results also strangely varies depending on the limit. For example, 3 results for limit 10 and 4 results for limit 15.

It seems this problem only occurs when the operation is set to all.

Proposal - what do you suggest to solve the problem or improve the existing situation?

There is similar issue #411, But I'm not sure and there is no response since Oct 13.
I found that difference in processing of query without operation caused by this line

jaeger/plugin/storage/cassandra/spanstore/reader.go

Line 265 in 4a07b78

if traceQuery.OperationName != "" {

So we use queryByServiceName query (or queryByTag if any tags are specified) instead of queryByServiceAndOperationName.
https://github.com/jaegertracing/jaeger/blob/50429cb55aee9280e39621a0b5aae3c2afe5d190/plugin/storage/cassandra/schema/v001.cql.tmpl
And as a consequence we selecting from service_name_index or tag_index instead of service_operation_index. They both use bucket strategy, may this be the reason?

Any open questions to address

[yurishkuro]

I think this is the same issue as #411

[morigs]

OK, but in #411 there is no activity from October 13. What to do next?
And I think that this is not a question, but definitely a bug.

[yurishkuro]

Lack of activity is not going to be helped by opening a duplicate ticket. Both tickets are duplicates of a much earlier ticket #166, a known issue.