JM1

Ansible Roles with OS-specific Defaults

This Ansible guide discusses several approaches on how to set different role default variables based / depending on the host operating system aka ansible_distribution / ansible_facts.distribution or other variables. For example, a role variable image_uri should point to the latest cloud image for the host. For CentOS 8 or Red Hat Enterprise Linux (RHEL) 8 the default value should be:

valyala

Optimizing postgresql table for more than 100K inserts per second

• Create UNLOGGED table. This reduces the amount of data written to persistent storage by up to 2x.
• Set WITH (autovacuum_enabled=false) on the table. This saves CPU time and IO bandwidth on useless vacuuming of the table (since we never DELETE or UPDATE the table).
• Insert rows with COPY FROM STDIN. This is the fastest possible approach to insert rows into table.
• Minimize the number of indexes in the table, since they slow down inserts. Usually an index on time timestamp with time zone is enough.
• Add synchronous_commit = off to postgresql.conf.
• Use table inheritance for fast removal of old data:

miguno

#!/usr/bin/env bash
#
# File:      kafka-move-leadership.sh
#
# Description
# ===========
#
# Generates a Kafka partition reassignment JSON snippet to STDOUT to move the leadership
# of any replicas away from the provided "source" broker to different, randomly selected
# "target" brokers.  Run this script with `-h` to show detailed usage instructions.