On 2/22/2018 10:45 AM, LOPEZ-CORTES Mariano-ext wrote:
For the moment, I have the following information:
12GB is max java heap. Total memory i don't know. No direct access to host.
2 replicas =
Size 1 = 11.51 GB
Size 2 = 11.82 GB
(Sizes showed in the Core-Overview admin gui)
OK, so you have about 23GB of total index data on the machine. With a
12GB heap, and assuming there's no other software running on the
machine, then for good performance I would want to have at least 32GB
total memory, which leaves around 20GB for the OS to cache the 23GB
index. More memory would be better, but probably isn't a requirement.
If there is other software running on the machine, then that will
increase the total memory requirement.
It is always possible that your Solr install is in a situation where
12GB of heap is actually not quite big enough. If that happens,
performance will usually be a lot worse than in situations where the
left-over memory is not enough for the OS to cache the index properly.
You might be able to get decent performance if the total memory is about
24GB, but that much might NOT be enough. There are a lot of factors
affecting actual memory requirements.
The Solr admin UI will tell you what the total physical memory in the
system is, on the dashboard. It will be the upper right graph. Note
that this graph is likely to show 100% or nearly 100% full. Don't let
this alarm you -- it's normal.
How did you arrive at the 12GB size for your heap? Have you tried
reducing this number so that there is more memory left for the OS to
handle disk caching? I have no idea whether your Solr install will
still work properly with a smaller heap, so be aware that reducing the
heap might cause more problems.