lucene-solr-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Caruana, Matthew" <>
Subject Re: What is the bottleneck for an optimise operation?
Date Thu, 02 Mar 2017 17:37:16 GMT
Thank you, these are useful tips.

We were previously working with a 4GB heap and getting OOMs in Solr while updating (probably
from the analysers) that would cause the index writer to close with what’s called a “tragic”
error in the writer code. Only a hard restart of the service could bring it back. There are
certain documents that function like poison and trigger this error every time. Haven’t had
time to isolate and create a test case, so throwing RAM at it is a stopgap.

When I do, I’ll file an issue.

> On 2 Mar 2017, at 18:28, Walter Underwood <> wrote:
> 6.4.0 added a lot of metrics to low-level calls. That makes many operations slow. Go
back to 6.3.0 or wait for 6.4.2.
> Meanwhile, stop running optimize. You almost certainly don’t need it.
> 24 GB is a huge heap. Do you really need that? We run a 15 million doc index with an
8 GB heap (Java 8u121, G1 collector). I recommend a smaller heap so the OS can use that RAM
to cache file buffers.
> wunder
> Walter Underwood
>  (my blog)
>> On Mar 2, 2017, at 7:04 AM, Caruana, Matthew <> wrote:
>> I’m currently performing an optimise operation on a ~190GB index with about 4 million
documents. The process has been running for hours.
>> This is surprising, because the machine is an EC2 r4.xlarge with four cores and 30GB
of RAM, 24GB of which is allocated to the JVM.
>> The load average has been steady at about 1.3. Memory usage is 25% or less the whole
time. iostat reports ~6% util.
>> What gives?
>> Running Solr 6.4.1.

View raw message