killing FUSEKI query

[Ewa Szwed <ew...@gmail.com>]

Hi,

Last question from me (at least in the near future).

I am thinking of designing a basic monitor for my Fuseki instance so that
people (and systems) could easily see what is the server load at any given
moment.
The idea is to expose a service that would read the Fuseki log file and/or
Jena log file to see for which queries there was no [no] 200 OK log entry.

My question is:
Is there a way to kill running query on the Fuseki or Jena level.
Regards,
Ewa

Re: killing FUSEKI query

[Andy Seaborne <an...@apache.org>]

>>> My question is:
>>> Is there a way to kill running query on the Fuseki or Jena level.
>>>
>>
>> Currently, you have to do it via your OS.  "kill -9" is fine.
>>
>
> I meant to kill individual Fuseki query,
> For my queries it might happen that client sends a query and drops, and
> such a query would execute for 2 hours and then EOF Exception is thrown.
> I would like to kill such a query from my monitor tool :)

Queries can be killed from Java - there is a method on a query execution 
to asynchronously kill it.  It's what the timeout mechanism uses.

There's no remote interface to the functionality.  Custom code 
integrated into the server could do it (assembler allow loading customer 
java).

To do it properly: the tricky bit is to identify the query remotely. As 
the log shows, every request gets a unique number so we could do the web 
thing and have /dataset/query/1234 be the URI of the query with suitable 
operations.

Such a mechanism does not exist currently - be nice to do though.  I 
need to do something for backups to make them async operations you can 
poll for completion.

	Andy

Re: killing FUSEKI query

[Ewa Szwed <ew...@gmail.com>]

Hi Andy, look inline.

2014-01-30 Andy Seaborne <an...@apache.org>:

> On 30/01/14 11:49, Ewa Szwed wrote:
>
>> Hi,
>>
>> Last question from me (at least in the near future).
>>
>
> Bluff :-)
>
>
>  I am thinking of designing a basic monitor for my Fuseki instance so that
>> people (and systems) could easily see what is the server load at any given
>> moment.
>> The idea is to expose a service that would read the Fuseki log file and/or
>> Jena log file to see for which queries there was no [no] 200 OK log entry.
>>
>
> Is this for timeouts?  You can set query timeouts which are applied quite
> aggressively.  Not perfect but it takes an increasingly ingenious client to
> block a query.


This is to monitor load in general.

>
>
>
>> My question is:
>> Is there a way to kill running query on the Fuseki or Jena level.
>>
>
> Currently, you have to do it via your OS.  "kill -9" is fine.
>

I meant to kill individual Fuseki query,
For my queries it might happen that client sends a query and drops, and
such a query would execute for 2 hours and then EOF Exception is thrown.
I would like to kill such a query from my monitor tool :)

>
> Development-in-progress is to completely rewrite the Fuseki UI and add an
> administrative interface.  And add security (Apache Shiro) because now
> there are operations that can damage a working service - shutdown being one
> of them.
>
> This is both UI and API for admin.  Stopping the server is part of that
> (may not be the first release).
>
> https://svn.apache.org/repos/asf/jena/branches/jena-fuseki-new-ui/
>
>         Andy
>
>  Regards,
>> Ewa
>>
>>
>

Re: killing FUSEKI query

[Andy Seaborne <an...@apache.org>]

On 30/01/14 11:49, Ewa Szwed wrote:
> Hi,
>
> Last question from me (at least in the near future).

Bluff :-)

> I am thinking of designing a basic monitor for my Fuseki instance so that
> people (and systems) could easily see what is the server load at any given
> moment.
> The idea is to expose a service that would read the Fuseki log file and/or
> Jena log file to see for which queries there was no [no] 200 OK log entry.

Is this for timeouts?  You can set query timeouts which are applied 
quite aggressively.  Not perfect but it takes an increasingly ingenious 
client to block a query.

>
> My question is:
> Is there a way to kill running query on the Fuseki or Jena level.

Currently, you have to do it via your OS.  "kill -9" is fine.

Development-in-progress is to completely rewrite the Fuseki UI and add 
an administrative interface.  And add security (Apache Shiro) because 
now there are operations that can damage a working service - shutdown 
being one of them.

This is both UI and API for admin.  Stopping the server is part of that 
(may not be the first release).

https://svn.apache.org/repos/asf/jena/branches/jena-fuseki-new-ui/

	Andy

> Regards,
> Ewa
>