Karan Singh

Where there's a Cloud , there's a way !!

Kubernetes : Deployment Using Ansible on VirtualBox by Vagrant

| Comments


Containers are everywhere. You will not find any tech event, tech meetup and tech discussion without using the word containers. Yes containers are almost ubiquitous. But containers alone will not solve your tech challenges, they need someone to give them ride. Containers are nothing but isolated gift box containing some present, they need someone to take care of the delivery to the right address. This is where container management/orchestration/scheduling systems comes into picture , Kubernetes, Mesos , Docker Swarm , Kontana are some examples of container orchestration systems.

Kubernetes is the new HOT container management system brought to you by Big Daddy Google. In this blog i will help you to get your hands dirty with Kubernetes (K8s). Here is what we are going to do

  • Setup a local environment using Vagrant and Virtualbox
  • Deploying K8s using Ansible
  • Interacting with K8s
  • Deploy your first application on K8s

OpenStack Summit Boston : Voting Begins

| Comments

openstack summit

Hello Stackers and Cephers , as you already know the next OpenStack summit is around the corner and is planned for 8-11 May , Boston MA. Its the Time to VOTE NOW.

This time i have submitted the following presentations which are very unique and touching different dimensions of your favorite technology .

Ceph User Group Finland : First Meetup

| Comments

My colleague Toni Willberg from Red Hat Finland office, came up with a brilliant idea of creating a Ceph local meetup group “Ceph user group Finalnd” , so we both pursued that idea and created Ceph user group Finland (CugF)

This is group that brings together software/devops/system engineers, cloud/solution architects with an interest in Ceph, software defined storage and data center storage infrastructure to collaborate and share their knowledge,experience and opinions about the future of storage.

On 15th February 2017, we organized our first meetup with 2 presentations + great discussion. Here are they :

  • I have presented “Ceph Introduction and Beyond” and here are the slides.

  • My friend Pietari Hyv√§rinen presented “Detailed view of operations in production scale Ceph systems with Grafana” (i will seek his permission before publishing his slides)

Special Thanks to @ToniWillberg for CugF + 8 different User Groups that he is running in Finland Metropolitian Area on a wide range of open source technologies.

What’s Next : In approx 2 months time we will schedule our second meetup. Along with snacks and beer ( call out for sponsors ) you will enjoy listening to some interesting topics. If you are based in Finland and want to be the part of this community, feel free to join and collaborate. We will be happy to see you :)

Ceph Object Storage : Part-II (Indexless Buckets)

| Comments

Indexless Bucket

This is episode-2 of Ceph Object Storage Blog Series , you can refer to episode-1 here where i have explained the internals of Ceph Object Storage and covering over Ceph Indexless Buckets feature. In this episode we will go through the implementation of Ceph indexless buckets

By default Ceph RGW creates standard indexed bucket ( i.e. non-indexless buckets ). These buckets can list the objects stored in them. Lets verify standard bucket before configuring indexless buckets.

Ceph Object Storage : Part-I (the Internals)

| Comments

Ceph Object Storage

There is some performance difference between pure RADOS writes ( ex. via RadosBench ) vs RGW writes. There are several factors contributing to this such as :

  • Object storage access protocols ( S3 / Swift ) have higher overheads than native RADOS writes
  • Client write requests are translated through RGW adds additional latency causing additional bottlenecks
  • The most important factor is that “RGW maintains bucket indices that needs to be updated every time when a write operation is done. And further more RADOS writes does not have this over head of maintaining indexes / metadata”

In this blog post i will talk about a new feature landed in Ceph Jewel v10.1.0 which is officially known as Indexless Buckets and unofficially as Blind Buckets. Before diving into indexless buckets let’s understand what RGW does under the covers with a write request.

Working With NUMA/CPU Pinning

| Comments


The term CPU pinning / process affinity / NUMA generally boils down to the same idea that In a multi socket system, application best performance can be achieved by allowing application threads to get execute on the CPU core which is as close as to its memory bank. In most of the cases Linux process scheduler is intelligent enough to do this , however if you do this manually by yourself , it’s most likely that you will enjoy luxury of increased application performance. Here are some of my notes describing steps required for process affinity setup

Verify how application (radosgw in my case) threads being executed currently. The 5th column psr which represents processor core.

for i in $(pgrep radosgw); do ps -mo pid,tid,fname,user,psr -p $i;done

Don't Underestimate the Power of Ceph Placement Groups

| Comments

Ceph PG

Today i would like to share findings from one of my curious testing, which came from this basic question.

How Placement Group count affects Ceph performance?

If you are reading this blog then i assume you know what Ceph is and how Ceph Placement Groups (PG) works.

It all started when me and my colleague Sir Kyle Bader were discussing around how to get more performance out of our Ceph cluster with the following environment details

How Application IO's Are Treated by IO Scheduler

| Comments


Recently i have been doing FIO benchmarking and i found that IOPS reported by FIO != IOPS reported by iostat . Which made me think Why The Heck ?

So here is my FIO job with bs=4M and seq write

$ fio --filename=/dev/sdb --name=write-4M --rw=write --ioengine=libaio --bs=4M --numjobs=1 --direct=1 --randrepeat=0  --iodepth=1 --runtime=100 --ramp_time=5 --size=100G --group_reporting

write-4M: (g=0): rw=write, bs=4M-4M/4M-4M/4M-4M, ioengine=libaio, iodepth=1
Starting 1 process
Jobs: 1 (f=1): [W(1)] [100.0% done] [0KB/220.3MB/0KB /s] [0/55/0 iops] [eta 00m:00s]
write-4M: (groupid=0, jobs=1): err= 0: pid=424038: Tue Jun  7 23:48:32 2016
  write: io=22332MB, bw=228677KB/s, iops=55, runt=100001msec

As you can see fio reported 55 iops

Deploy COSBench Using Ansible

| Comments


In my previous blog about COSBench , i gave an introduction to this tool and have explained how you can install it and get it working.

Recently i automated COSBench installation and configuration using ansible and have created an ansible role. With this blog i will demonstrate how you can get COSBench up and running with minimal steps … because Ansible Rocks 8-)