Blocked NTR request

[Guan Sun <xs...@gmail.com>]

Hi,

I'm using Cassandra 2.2.8 with default NTR queque configurations (
max_queued_native_transtport_requests = 128, native_transport_max_threads =
128), and from the metrics I'm seeing some native transport requests are
being blocked.

I'm trying to understand what happens to the blocked native transport
requests, will these requests be rejected immediately so client get
exceptions/errors from Cassandra? or will these requests be waiting
somewhere outside of the queue and will be added to the NTR queue later? or
will these requests simply timeout after some time?

Any help would be appreciated!

Thanks,
Guan

Re: Blocked NTR request

[Laxmikant Upadhyay <la...@gmail.com>]

As per my understanding, Blocked requests do not get rejected immediately
and waits for some queued request to complete. And a request will timeout
only when the request creation time crosses configured request timeout.

You may try to tune the pool by increasing
max_queued_native_transtport_requests value if you see blocked NTR.

On Wed, Dec 12, 2018 at 12:07 AM Guan Sun <xs...@gmail.com> wrote:

> Hi,
>
> I'm using Cassandra 2.2.8 with default NTR queque configurations (
> max_queued_native_transtport_requests = 128, native_transport_max_threads
> = 128), and from the metrics I'm seeing some native transport requests
> are being blocked.
>
> I'm trying to understand what happens to the blocked native transport
> requests, will these requests be rejected immediately so client get
> exceptions/errors from Cassandra? or will these requests be waiting
> somewhere outside of the queue and will be added to the NTR queue later? or
> will these requests simply timeout after some time?
>
> Any help would be appreciated!
>
> Thanks,
> Guan
>


-- 

regards,
Laxmikant Upadhyay