docValuesFormat="Memory" has been deprecated, so you shouldn't use it.
On Tue, Nov 6, 2018 at 2:14 PM Wei <weiwan...@gmail.com> wrote:
>
> I see there is also a docValuesFormat option, what's the default for this
> setting? Performance wise is it good to set docValuesFormat="Memory" ?
>
> Best,
> Wei
>
>
> On Tue, Nov 6, 2018 at 11:55 AM Erick Erickson <erickerick...@gmail.com>
> wrote:
>
> > Yes, "the most efficient possible" is associated with that JIRA, so only
> > in 7x.
> >
> > "Does this still hold if whole index is loaded into memory?"
> > The decompression part yes, the disk seek part no. And it's also
> > sensitive to whether the documentCache already has the document.
> >
> > I'd also make uniqueKey ant the _version_ fields docValues.
> >
> > Best,
> > Erick
> > On Tue, Nov 6, 2018 at 10:44 AM Wei <weiwan...@gmail.com> wrote:
> > >
> > > Thanks Yasufumi and Erick.
> > >
> > > ---. 2. "it depends". Solr will try to do the most efficient thing
> > > possible. If _all_ the fields are docValues, it will return the stored
> > > values from the docValues structure.
> > >
> > > I find this jira: https://issues.apache.org/jira/browse/SOLR-8344
> > Does
> > > this mean "Solr will try to do the most efficient thing possible" only
> > > working for 7.x? Is the behavior available for 6.6?
> > >
> > > -- This prevents a disk seek and decompress cycle.
> > >
> > > Does this still hold if whole index is loaded into memory? Also for the
> > > benefit of performance improvement, does the uniqueKey field need to be
> > > always docValues? Since it is used in the first phase of distributed
> > > search.
> > >
> > > Thanks,
> > > Wei
> > >
> > >
> > >
> > > On Tue, Nov 6, 2018 at 8:30 AM Erick Erickson <erickerick...@gmail.com>
> > > wrote:
> > >
> > > > 2. "it depends". Solr will try to do the most efficient thing
> > > > possible. If _all_ the fields are docValues, it will return the stored
> > > > values from the docValues structure. This prevents a disk seek and
> > > > decompress cycle.
> > > >
> > > > However, if even one field is docValues=false Solr will by default
> > > > return the stored values. For the multiValued case, you can explicitly
> > > > tell Solr to return the docValues field.
> > > >
> > > > Best,
> > > > Erick
> > > > On Tue, Nov 6, 2018 at 1:46 AM Yasufumi Mizoguchi
> > > > <yasufumi0...@gmail.com> wrote:
> > > > >
> > > > > Hi,
> > > > >
> > > > > > 1. For schema version 1.6, useDocValuesAsStored=true is default, so
> > > > there
> > > > > > is no need to explicitly set it in schema.xml?
> > > > >
> > > > > Yes.
> > > > >
> > > > > > 2. With useDocValuesAsStored=true and the following definition,
> > will
> > > > Solr
> > > > > > retrieve id from docValues instead of stored field?
> > > > >
> > > > > No.
> > > > > AFAIK, if you define both docValues="true" and stored="true" in your
> > > > > schema,
> > > > > Solr tries to retrieve stored value.
> > > > > (Except using streaming expressions or /export handler etc...
> > > > > See:
> > > > >
> > > >
> > https://lucene.apache.org/solr/guide/6_6/docvalues.html#DocValues-EnablingDocValues
> > > > > )
> > > > >
> > > > > Thanks,
> > > > > Yasufumi
> > > > >
> > > > >
> > > > > 2018年11月6日(火) 9:54 Wei <weiwan...@gmail.com>:
> > > > >
> > > > > > Hi,
> > > > > >
> > > > > > I have a few questions about using the useDocValuesAsStored option
> > to
> > > > > > retrieve field from docValues:
> > > > > >
> > > > > > 1. For schema version 1.6, useDocValuesAsStored=true is default, so
> > > > there
> > > > > > is no need to explicitly set it in schema.xml?
> > > > > >
> > > > > > 2. With useDocValuesAsStored=true and the following definition,
> > will
> > > > Solr
> > > > > > retrieve id from docValues instead of stored field? if fl= id,
> > title,
> > > > > > score, both id and title are single value field:
> > > > > >
> > > > > > <field name="id" type="string" indexed="true" stored="true"
> > > > > > docValues="true" required="true"/>
> > > > > >
> > > > > > <field name="title" type="string" indexed="true" stored="true"
> > > > > > docValues="true" required="true"/>
> > > > > >
> > > > > > Do I need to have all fields stored="false" docValues="true" to
> > make
> > > > solr
> > > > > > retrieve from docValues only? I am using Solr 6.6.
> > > > > >
> > > > > > Thanks,
> > > > > > Wei
> > > > > >
> > > >
> >
