we faced into a lot of lwlock:LockManager wait-events , all of these queries are "select ..." , there are other several session are doing DML, insert/update/delete on same table. Did these DML transactions holding "transactionid" and "tuple" lock blocking "select" on lwlock:LockManager ?
Which version of PostgreSQL?
Are these all same query or variant of same query (with different parameters)?
What's the schema (you can redact column names) for the tables involved in the select query which is blocked/waiting on lock_manager?
