lucene-solr-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Walter Underwood <wun...@wunderwood.org>
Subject Re: solr crashes
Date Wed, 05 Dec 2018 16:11:33 GMT
I’ve never heard a recommendation to have three times as much RAM as the heap. That doesn’t
make sense to me.

You might need 3X as much disk space as the index size.

For RAM, it is best to have the sum of:

* JVM heap
* A couple of gigabytes for OS and demons
* RAM for other processes needed on the host (keep to a minimum)
* Enough RAM to hold the entire index

Clearly, you are not going to have enough RAM for a 555 gigabyte index. Well, Amazon does
have a dozen instance types that can do that, but they are expensive.

A 24 GB heap on a 30 GB machine will be pretty tight.

Always set Xms (starting heap) to the same as Xmx (maximum heap). If you set it smaller, the
JVM will keep increasing the heap until it hits the max before doing a full GC. It will always
end up with the max setting, but it will have to do more work to get there. The setting for
initial heap size is about the most useless thing in Java.

wunder
Walter Underwood
wunder@wunderwood.org
http://observer.wunderwood.org/  (my blog)

> On Dec 4, 2018, at 6:06 AM, Bernd Fehling <bernd.fehling@uni-bielefeld.de> wrote:
> 
> Hi Danilo,
> 
> Full GC points out that you need more heap which also implies that you need more RAM.
> Raise your heap to 24GB and your physical RAM to about 75GB or better 96GB.
> RAM should be about 3 to 4 times heap size.
> 
> Regards, Bernd
> 
> 
> Am 04.12.18 um 13:37 schrieb Danilo Tomasoni:
>> Hello Bernd,
>> Here I list the extra info you requested:
>> - actually the virtual machine has 22GB of RAM and 16GB of heap
>> - my 40 million raw data takes about 1364GB on filesystem (in xml format)
>> - my index optimized (1 segment, 0 deleted docs) takes about 555GB
>> - solr 7.3, openjdk 1.8.0_181
>> - GC logs are like
>> 2018-12-03T07:40:22.302+0100: 28752.505: [Full GC (Allocation Failure) 2018-12-03T07:40:22.302+0100:
28752.505: [CMS: 12287999K->12287999K(12288000K), 13.6470083 secs] 15701375K->15701373K(15701376K),
[Metaspace: 37438K->37438K(1083392K)], 13.6470726 secs] [Times: user=13.66 sys=0.00, real=13.64
secs]
>> Heap after GC invocations=2108 (full 1501):
>>  par new generation   total 3413376K, used 3413373K [0x00000003d8000000, 0x00000004d2000000,
0x00000004d2000000)
>>   eden space 2730752K,  99% used [0x00000003d8000000, 0x000000047eabfdc0, 0x000000047eac0000)
>>   from space 682624K,  99% used [0x000000047eac0000, 0x00000004a855f8a0, 0x00000004a8560000)
>>   to   space 682624K,   0% used [0x00000004a8560000, 0x00000004a8560000, 0x00000004d2000000)
>>  concurrent mark-sweep generation total 12288000K, used 12287999K [0x00000004d2000000,
0x00000007c0000000, 0x00000007c0000000)
>>  Metaspace       used 37438K, capacity 38438K, committed 38676K, reserved 1083392K
>>   class space    used 4257K, capacity 4521K, committed 4628K, reserved 1048576K
>> }
>> Thank you for your help
>> Danilo
>> On 03/12/18 10:36, Bernd Fehling wrote:
>>> Hi Danilo,
>>> 
>>> you have to give more infos about your system and the config.
>>> 
>>> - 30gb RAM (physical RAM?) how much heap do you have for JAVA?
>>> - how large (in GByte) are your 40 million raw data being indexed?
>>> - how large is your index (in GByte) with 40 million docs indexed?
>>> - which version of Solr and JAVA?
>>> - do you have JAVA garbage collection logs and if so what are they reporting?
>>> - Any FullGC in GC logs?
>>> 
>>> Regards, Bernd
>>> 
>>> 
>>> Am 03.12.18 um 10:09 schrieb Danilo Tomasoni:
>>>> Hello all,
>>>> 
>>>> We have a configuration with a single node with 30gb of RAM.
>>>> 
>>>> We use it to index ~40MLN of documents.
>>>> 
>>>> We perform queries with edismax parser that contain often edismax parser
subqueries with the syntax
>>>> 
>>>> '_query_:{!edismax mm=X v=$subqueryN}'
>>>> 
>>>> Often X == 1.
>>>> 
>>>> This solves the "too many boolean clauses" error we got expanding the query
terms (often phrase queries) directly in the main query.
>>>> 
>>>> Unfortunately in this scenario solr often crashes while performing a query,
even with a single query and no other source of system load.
>>>> 
>>>> 
>>>> Do you have any idea of what's going on here?
>>>> 
>>>> Otherwise,
>>>> 
>>>> What kind of solr configuration parameters do you think I need to investigate
first?
>>>> 
>>>> What kind of log lines should I search for to understand what's going on?
>>>> 
>>>> 
>>>> Thank you
>>>> 
>>>> Danilo
>>>> 
> 
> -- 
> *************************************************************
> Bernd Fehling                    Bielefeld University Library
> Dipl.-Inform. (FH)                LibTec - Library Technology
> Universitätsstr. 25                  and Knowledge Management
> 33615 Bielefeld
> Tel. +49 521 106-4060       bernd.fehling(at)uni-bielefeld.de
>          https://www.ub.uni-bielefeld.de/~befehl/
> 
> BASE - Bielefeld Academic Search Engine - www.base-search.net
> *************************************************************


Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message