Re: Segfault in MergedIterator.pullTop()

[Adrien Grand <jp...@gmail.com>]

In the past weeks we got more and more reports of this segfault. It
manifests with JDK 10 and processors that support AVX-512 instructions. For
instance this bug has been reproduced by several users on AWS C5 and M5
instances.

I have no reason to think that only Elasticsearch is affected. Solr and
other Lucene-based applications are probably affected too. It can be worked
around by passing -XX:UseAVX=2 to the JVM arguments.

This bug is tracked at https://bugs.openjdk.java.net/browse/JDK-8207746.
Kudos to Jason Tedor for digging and reporting this bug.

Le mer. 20 juin 2018 à 11:05, Adrien Grand <jp...@gmail.com> a écrit :

> FYI we have had 3 independent reports of segfaults in
> org.apache.lucene.util.MergedIterator.pullTop() when running Elasticsearch
> with Java 10. Here is one of them:
> https://github.com/elastic/elasticsearch/issues/31425. It's still unclear
> to me what conditions need to be met for this bug to reproduce. I'm
> wondering whether anyone has seen this JVM bug before? For the record,
> Elasticsearch doesn't use MergedIterator explicitly, it only gets used via
> MultiFields when merging terms.
>

Re: Segfault in MergedIterator.pullTop()

[David Smiley <da...@gmail.com>]

Thanks for spreading the word!

On Tue, Jul 17, 2018 at 4:35 PM Adrien Grand <jp...@gmail.com> wrote:

> In the past weeks we got more and more reports of this segfault. It
> manifests with JDK 10 and processors that support AVX-512 instructions. For
> instance this bug has been reproduced by several users on AWS C5 and M5
> instances.
>
> I have no reason to think that only Elasticsearch is affected. Solr and
> other Lucene-based applications are probably affected too. It can be worked
> around by passing -XX:UseAVX=2 to the JVM arguments.
>
> This bug is tracked at https://bugs.openjdk.java.net/browse/JDK-8207746.
> Kudos to Jason Tedor for digging and reporting this bug.
>
> Le mer. 20 juin 2018 à 11:05, Adrien Grand <jp...@gmail.com> a écrit :
>
>> FYI we have had 3 independent reports of segfaults in
>> org.apache.lucene.util.MergedIterator.pullTop() when running Elasticsearch
>> with Java 10. Here is one of them:
>> https://github.com/elastic/elasticsearch/issues/31425. It's still
>> unclear to me what conditions need to be met for this bug to reproduce. I'm
>> wondering whether anyone has seen this JVM bug before? For the record,
>> Elasticsearch doesn't use MergedIterator explicitly, it only gets used via
>> MultiFields when merging terms.
>>
> --
Lucene/Solr Search Committer, Consultant, Developer, Author, Speaker
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