cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Chris Lohfink <clohfin...@gmail.com>
Subject Re: How to get information of each read/write request?
Date Tue, 30 Aug 2016 19:31:17 GMT
Running a query with trace (`TRACING ON` in cqlsh) can give you a lot of
the information for an individual request. There has been a ticket to track
time in queue (https://issues.apache.org/jira/browse/CASSANDRA-8398) but no
ones worked on it yet.

Chris

On Tue, Aug 30, 2016 at 12:20 PM, Jun Wu <wuxiaomin98@hotmail.com> wrote:

> Hi there,
>
>      I'm very interested in the read/write path of Cassandra.
> Specifically, I'd like to know the whole process when a read/write request
> comes in.
>
>     I noticed that for reach request it could go through multiple stages.
> For example, for read request, it could be in ReadStage,
> RequestResponseStage, ReadRepairStage. For each stage, actually it's a
> queue and thread pool to serve the request.
>
>    First question is how to track each request in which stage.
>
>    Also I'm very interested int the waiting time for each request to be in
> the queue, also the total queue in each stage. I noticed that in nodetool
> tpstats will have this information. However, I may want to get the
> real-time information of this, like print it out in the terminal.
>
>     I'm wondering  whether someone has hints on this.
>
>    Thanks in advance!
>
> Jun
>
>
>

Mime
View raw message