[DOC] Fix default values for filter cache size and field data circuit breaker.

Relates to #5990

docs/reference/index-modules/cache.asciidoc

@@ -24,7 +24,7 @@ when a cache becomes full, the least recently used data is evicted to
 make way for new data.
 
 The setting that allows one to control the memory size for the filter
-cache is `indices.cache.filter.size`, which defaults to `20%`. *Note*,
+cache is `indices.cache.filter.size`, which defaults to `10%`. *Note*,
 this is *not* an index level setting but a node level setting (can be
 configured in the node configuration).
 

docs/reference/index-modules/fielddata.asciidoc

@@ -30,7 +30,7 @@ example, can be set to `5m` for a 5 minute expiry.
 The field data circuit breaker allows Elasticsearch to estimate the amount of
 memory a field will required to be loaded into memory. It can then prevent the
 field data loading by raising and exception. By default the limit is configured
-to 80% of the maximum JVM heap. It can be configured with the following
+to 60% of the maximum JVM heap. It can be configured with the following
 parameters:
 
 [cols="<,<",options="header",]