Re: "timeAllowed" param with "numFound" having a count value but doc list is empty

[Aleksandr Yaroslavskiy <ay...@gmail.com>]

Hi,
I am using timeAllowed and a collection with shards.
Docs list contains results only if QTime(query time) < timeAllowed.
In other cases (partialResults=true in responseHeader) docs are empty.

/solr/collection_with_shards/select?etimeAllowed=1000&q=some_slow_query
docs is empty

If access a specific shard and ask for data only from it:
/solr/collection_with_shards_shard1/select?shards=shard1&timeAllowed=1000&q=some_slow_query
docs list contains results! (partialResults=true)

If add debug=all to the collection query:
/solr/collection_with_shards/select?timeAllowed=1000&debug=all&q=some_slow_query
then docs list empty, but in debug info all the shards returned lists of
document id's with weights.

Tested on solr 8.4 and solr 8.7, change timeAllowed from 100 то 3000.
Always if QTime>timeAllowed docs list empty.

Results from individual shards never have time to process for the general
docs list or am I doing something wrong?

Can anyone confirm that when QTime>timeAllowed and count(shards)>1 you can
get a nonempty docs list?

Date: Tue, 15 Sep 2020 23:38:23 +0200
Dominique Bejean <do...@eolya.fr>
wrote:

>Hi,
>
>1. Yes, your analysis is correct
>
>2. Yes, it can occurs too with very slow query.
>
>Regards
>
>Dominique
>
>Le mar. 15 sept. 2020 à 15:14, Mark Robinson <ma...@gmail.com> a
>écrit :

>> Hi,
>>
>> When in a sample query I used "timeAllowed" as low as 10mS, I got value
for
>>
>> "numFound" as say 2000, but no docs were returned. But when I increased
the
>>
>> value for timeAllowed to be in seconds, never got this scenario.
>>
>>
>>
>> I have 2 qns:-
>>
>> 1. Why does numFound have a value like say 2000 or even 6000 but no
>>
>> documents actually returned. During document collection is calculation of
>>
>> numFound done first and doc collection later?. Is doc list empty
because,by
>>
>> the time doc collection started the timeAllowed cut off took effect?
>>
>>
>>
>> 2. If I give timeAllowed a value say, 10s or above do you think the above
>>
>> scenario of valid count displayed in numFound, but doc list empty can
ever
>>
>> occur still, as there is more time before cut-off to retrieve at least
one
>>
>> doc ?
>>
>>
>>
>> Thanks!
>>
>> Mark