Ceph is free if your time is worth nothing!

Ironic how we grow up listening to our parent’s tell us “Nothing in life is free” yet the moment someone claims they have or do something for “free”, we forget that simple truth.

Is anything ever really free?
There are offerings out there today that claim they are open source, free and always will be. However, if we remember what Mom and Dad said – then we need to look deeper into this. Time, overhead and hardware requirements to run these open source solutions are not free.

For this discussion, let us take a look at Ceph and Ceph “Enterprise” editions. Ceph is an open source distributed object store and file system which claims to be free. As an open source platform the code is indeed free but if Ceph is free, why would any company pay to acquire a “commercial wrapper” for it, such as Inktank? When it comes to open source, large companies make their money by selling “enhanced” versions of the software along with professional consulting, services, and support.

Enterprise versions are not free and often expensive. Customers pay more in server hardware, server OS licenses & disk drives. Licensing and support can run as much as $4K per server.

Now, some will say, “I will go with the free version of the open source solution and not the “enhanced” or “enterprise” edition offered – it’s more cost effective and I can support it myself”. It is definitely an option, and in some instances may make sense, but before you make that commitment ask yourself:
• Can I get 24×7 worldwide support – the support I need, when I need it?
• Do I have to wait for a community to help solve my problem and even if a fix is suggested, will it work for me, in my environment?
• Will my customers wait till tomorrow or the next week for a fix?
• Does ‘ongoing support by committee’ really work?
• What am I willing to give up?

If it is free – do you get what you pay for?Car

When it comes to software-defined scale out block storage for high performing applications and / or delivering Infrastructure-as-a-Service (IaaS), “free” may not be better. Will you simply be getting what you pay for?

Starting with installation, as a software-defined offering, Ceph does not constrain or confine you like current hyper-converged appliances do. However, installation is actually extremely complex. Architecting and running Ceph as a storage platform requires deep Linux and Ceph expertise and experience. It requires a multi module, multi-step, deployment process (with different processes for each OS) which complicates management and incurs a larger performance hit to the underlying hardware. Ceph also takes a ‘non-native’ layered approach to delivering block storage, where block is on top of object. David Noy, VP Product Management at EMC pointed out in his blog last month, that with a layered approach “problems come when you have a system that is designed to optimize around the underlying abstraction and not the service layered on top”. This is evident in Ceph’s approach to block (RADOS Block Device – RBD) which has extreme overhead resulting in high latency and an inability to exploit Flash media.

OK, so you know there will be a great deal of work to set up and manage Ceph. You still feel you are ready to deal with this cryptic approach including: compile/decompile/manually edit crush maps; limited system visibility using a command line interface (CLI); and even the manual placement group (PG) planning and repair. Yes, the free approach, even with all of this, will meet your needs. Maybe but let’s not forget what really matters. When delivering IaaS or high performance applications, delays in response are simply not acceptable to your customers or users. How does Ceph measure up where it really counts: Performance and Scalability!

The Proof is in the Numbers
We recently tested Ceph against EMC ScaleIO and the findings were clear as day. Both were tested on the same hardware and configuration with the following assumptions:
• Test “SSD only” using a small volume that will fit the SSD capacity
• Test “SSD+HDD” using a small+large volume spanning HDD capacity
• Test SSD as Cache for HDD using a small+large volume spanning HDD cap
• Test a Mixed workload of 70% Reads, 30% Writes, 8KB IOs

Findings:
• ScaleIO achieved ~7X better performance than the best Ceph IOPs value for a drive limited configuration
• ScaleIO achieved ~15X better performance than Ceph, when the drives are not the limit
• ScaleIO has ~24X better Response Time with an SSD only configuration
• ScaleIO can support the IOPs at 1/3rd the latency of Ceph, as a result there is no need to second guess performance for applications you run on ScaleIO.

Similar to Ceph, EMC ScaleIO is a software-only solution that uses existing commodity hardware servers’ local disks and LAN to realize a software-defined, scale-out SAN. However, EMC ScaleIO delivers elastic and scalable performance and capacity on demand and beyond what Ceph is a capable of for enterprise deployments. ScaleIO also does not require additional servers for providing storage and supports multiple platforms including OpenStack via a Cinder Plugin. It requires 1/5th to 1/10th the number of drives that Ceph needs to deliver the same performance. This actually results in significant floor and power savings.

The evidence speaks for itself when it comes to performance, scale and enterprise grade capabilities – sometimes you just get what you pay for. But don’t just take our word for it. Here is a perfect example of the kind of issues a company can face, including the potential loss of date, when delivering services with Ceph. Also, Enterprise Strategy Group (ESG) recently published a Lab Spotlight demonstrating extremely high IOPS performance and near-linear scaling capabilities of ScaleIO software on commodity hardware.

If you STILL want to be able use software for free BEFORE you make a long term, strategic commitment, EMC provides you the same opportunity with ScaleIO. May 2015, EMC is offering a free download of ScaleIO, for non-production use, for as much capacity and time as you want. You can experience all of the features and capabilities and see for yourself why enterprise grade software-defined scale out SAN with EMC ScaleIO is better than “free” with Ceph. Virtual Geek is ready! Are you?

About the Author: Jyothi Swaroop