Update gc.md

Author: mincong-h

ops/gc.md

@@ -1,28 +1,3 @@
 # GC
 
-## Flag Lookup
-
-Find the default value of a GC setting in Java:
-
-```sh
-java -XX:+PrintFlagsFinal -version
-```
-
-For example, finding the default value of `MaxGCPauseMillis` can be done as follow:
-
-```sh
-~ $ java -XX:+PrintFlagsFinal -version | grep MaxGCPauseMillis
-    uintx MaxGCPauseMillis                         = 200                                       {product} {default}
-openjdk version "14.0.2" 2020-07-14
-OpenJDK Runtime Environment AdoptOpenJDK (build 14.0.2+12)
-OpenJDK 64-Bit Server VM AdoptOpenJDK (build 14.0.2+12, mixed mode, sharing)
-```
-
-## Articles
-
-- Elasticsearch, "GC logging", _Elasticsearch_, 2020.<br>
-  <https://www.elastic.co/guide/en/elasticsearch/reference/current/gc-logging.html>
-- Oracle, "Concurrent Mark Sweep (CMS) Collector (Java 8)", _Oracle_, 2020.<br>
-  <https://docs.oracle.com/javase/8/docs/technotes/guides/vm/gctuning/cms.html>
-- Prabin Meitei M, "Garbage Collection in Elasticsearch and the G1GC", _Medium_, 2018.<br>
-  <https://medium.com/naukri-engineering/garbage-collection-in-elasticsearch-and-the-g1gc-16b79a447181>
+<https://mincong.io/2020/08/30/gc-in-elasticsearch/>