how to understand checkpoint information in pg_control data

From: Pavan Kumar <pavan(dot)dba27(at)gmail(dot)com>
To: pgsql-general(at)lists(dot)postgresql(dot)org, Pgsql-admin <pgsql-admin(at)lists(dot)postgresql(dot)org>
Subject: how to understand checkpoint information in pg_control data
Date: 2019-06-28 15:09:51
Message-ID: CA+M0sHEpzKNi8zq2jM4JnyBmqb3tPLohRx1JU0SdGzY0w1Re6g@mail.gmail.com
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Hello Experts,

I have couple of questions on pg_controldata output.

postgres=# \! pg_controldata $PGDATA|grep checkpoint

*Latest checkpoint location: 2/9D029BB0, Latest checkpoint's
REDO location: 2/97002D60Latest checkpoint's REDO WAL file:
000000030000000200000097 *
Latest checkpoint's TimeLineID: 3
Latest checkpoint's PrevTimeLineID: 3
Latest checkpoint's full_page_writes: on
Latest checkpoint's NextXID: 0:1732072
Latest checkpoint's NextOID: 40985
Latest checkpoint's NextMultiXactId: 1
Latest checkpoint's NextMultiOffset: 0
Latest checkpoint's oldestXID: 561
Latest checkpoint's oldestXID's DB: 1
Latest checkpoint's oldestActiveXID: 1731942
Latest checkpoint's oldestMultiXid: 1
Latest checkpoint's oldestMulti's DB: 1
Latest checkpoint's oldestCommitTsXid:0
Latest checkpoint's newestCommitTsXid:0
Time of latest checkpoint: Fri 28 Jun 2019 02:59:24 PM GMT

What is "Latest checkpoint location"
what is "Latest checkpoint's REDO location". to my understanding, it is
records lsn number. correct me if I am wrong?
Latest checkpoint's REDO WAL file: 000000030000000200000097, to my
understanding this wal file has the latest record lsn , from where
recovery will start and rollover. please correct me if I am wrong ?

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