I'm transitioning my index from a 3.x version to >4.6. I'm running a large heap (20G), primarily to accomodate a large facet cache (~5G), but have been able to run it on 3.x stably.
On 4.6.0 after stress testing I'm finding that all of my shards are spending all of their time in GC. After taking a heap dump and analyzing, it appears that org.apache.lucene.util.WeakIdentityMap is using many Gs of memory. Does anyone have any insight into which Solr component(s) use this and whether this kind of memory consumption is to be expected? Thank You, -Harish
