Perf Degradation - Decrease in throughput for COUNTER incr operation by 20%

Functions executed/sec, 1 bucket x 100M x 1KB, 4KV + 1Eventing node, Counter Increment 0% Contention - is seeing the perf degradation

The regressions seems to be coming from this : http://changelog.build.couchbase.com/?product=couchbase-server&fromVersion=7.0.0&fromBuild=3696&toVersion=7.0.0&toBuild=3701&f_asterixdb=off&f_backup=off&f_build=off&f_cbas-core=off&f_cbbs=off&f_cbft=off&f_cbgt=off&f_couchstore=off&f_eventing=on&f_goxdcr=off&f_indexing=off&f_kv_engine=off&f_magma=off&f_ns_server=off&f_query=off&f_testrunner=off change. We see this degradation only in counter increment non src bkt mutation test.

That change was to fix the memory leak that caused the increase in consumer rss in src bkt mutation cases. But it is seen to regress counter increment performance in the non src bkt test.