Oracle Storage Guy

VMware: Maritz out, Gelsinger in. What does it mean for Oracle?

As many of you have heard by now, Paul Mauritz is out as CEO of VMware, and Pat Gelsinger (formerly COO of EMC, reporting directly to Joe Tucci) is replacing him.

The relevant question for those of us who care passionately about Oracle virtualization using VMware vSphere is:

What does this mean for VMware's BCA (Business Critical Applications: stuff like Oracle) strategy (which under Maritz was somewhat lacking)?

In my view, this is very, very good news indeed. The reason is simple: Paul Maritz was former Microsoft, and thus very Microsoft-centric. Under Maritz, VMware very successfully penetrated the Microsoft space (especially Exchange). BCA, and especially Oracle were not that well supported by VMware's high level leadership in my view.

There is no question in my mind that Pat Gelinger gets it with respect to the importance of Oracle for VMware's future. (As I have said before, I believe that Oracle is the most interesting virtualization target environment for VMware, period.)

Gelsinger has shown consistent interest in Oracle, as his presentation at Oracle OpenWorld 2011 shows. (His co-presentation which included a vCenter demo with Chad Sakac at OOW 2011 is classic.)

We wish Pat Gelinger the very best in his new role and have high hopes for him as the leader of VMware.

NetApp's ExaData Backup Play Reprise

I have received a fair number of responses to my previous post on this subject (some via comments and some via email). I thought the discussion worthwhile enough to punch it up a bit more here.

Backup

As I pointed out in the previous post, EMC can easily match NetApp's play to back up ExaData with the following:

As Geoff Rosser so correctly pointed out, this answer is incomplete. Yes, Data Domain is an awesome Oracle backup solution. Yes, it provides incredible deduplication rates for Oracle database environments. (Thanks, dynamox.) However, it is not the only viable solution from EMC for backing up ExaData. For example, the following would also work:

As usual comments are welcome.

NetApp's ExaData Backup Play

There has been lots of material on the web recently concerning NetApp being able to backup ExaData. The purpose of this blog is to respond to that content, and state why NetApp's offering is rather lame, and actually offers nothing new.

The items on the web produced by NetApp are easy to find. I will not increase their Google hit rate by linking to them here. Suffice it to say, Neil Gerren's blog contains the principle content to which I will respond here. There is also NetApp technical report TR 4022, a 34 page tome, which I have read thoroughly. I think I completely understand what NetApp has produced (which they thought so much of to produce a press release on the subject), and, believe me, there is nothing new or unique in NetApp's offering.

I will summarize the solution here. To avoid any issues with NetApp copyrights, I have recreated the graphics describing the solution. However, the gist is identical to that contained in TR 4022. The solution consists of two parts:

• Backup
• Disaster recovery / remote replication

Backup

Let's start with the backup component. What NetApp proposes is the following:

The fundamental gist of the solution is:

• Connect ExaData to a NetApp filer using 10 GbE.
• Backup the Oracle database on the ExaData to the NetApp filer using RMAN.

I ask you: Is there anything interesting or unique here? In fact, I would state for the record that it would be manifestly better to do the following:

In other words, an EMC Data Domain deduplication array is capable of connecting to an ExaData box and backing it up using RMAN in exactly the same manner as a NetApp filer. I find this statement so obvious that it seems self-evident. But, again, NetApp's material on the subject makes it necessary to point this out.

Data Domain has many advantages over NetApp in the area of Oracle backup. But I will not belabor that point. Suffice it to say, we can do the same thing that NetApp can in the area of backing up Oracle ExaData via 10 GbE. And we certainly have a product which is very suited to backing up Oracle database data, and commonly used for this purpose.

Disaster Recovery / Remote Replication

Let's turn now to the disaster recovery / remote replication solution. What NetApp proposes for a disaster recovery / remote replication solution looks like this:

The fundamental gist of the solution is: 

• Replicate the production Oracle databse on ExaData using Oracle Data Guard with physical standby. The target platform consists of generic Intel x86 servers running Linux. (Remember that the RAC compute nodes in the ExaData are nothing more than relatively typical x86 / Linux servers. Thus, Oracle Data Guard with physical standby to a similar non-Oracle server will work just fine, it being an identical platform from an Oracle point of view.)
• The target database server is connected to a NetApp filer using standard protocols (e.g. FC or NFS).
• Once the database copy is on the NetApp filer, normal NetApp tools can be used to snap, clone, etc. the target database.

Again. it seems rather patently obvious that the following is also possible:

And in terms of the ability to perform snaps, clones, and so forth of the Oracle database once it is on our array, EMC's arrays contain features that easily meet those offered by NetApp.

So, again, NetApp's highly touted offering concerning storing ExaData offers nothing new or unique. Each and every feature offered by NetApp is available from EMC, and many features offered by EMC are superior to those provided by NetApp.

Comments to this post are welcome.

 

Is ExaData an "Appliance"

My boss, Sam Lucido, raised the following question on the Everything Oracle at EMC website:

Appliances such as microwave ovens, refrigerators, iPods, iPads and TVs are excellent examples of the ease-of-use approach. Bringing the inherently complex world of Oracle databases together with the ease-of-use approach of appliances is challenging. By definition if Oracle Exadata is an appliance then its use should be simple, require relatively little maintenance and like a refrigerator do its job which in this case is run databases at extreme performance levels. If Oracle Exadata isn’t an appliance than what is it?

I found this question quite compelling. Remember that I really grew up in a truly appliance-oriented environment (NetApp). See my first blog posts for more information on my background at NetApp. For this reason, I think I understand what an appliance is pretty well.

At NetApp (and during my early days at NetApp, filers were true appliances by any measure), the appliance concept meant that the device was a toaster: One lever to push down, and one knob to turn. That's it. Plug it in. It works. No step 2.

Cisco really originated the term appliance. The Cisco router replaced the previous form of router, which was typically a UNIX box running routed. As such, the Cisco router pretty much defined the concept of what it means to be a true appliance.

The folks at Cisco made the following argument: We don't need all of the infrastructure of UNIX to do routing. A UNIX box has to do a lot of things. A router really only has to do one thing: Networking. We could make a dramatically simplified device which would be able to do routing really well, at a much lower cost than a UNIX box.

Based upon this concept, an appliance has the following characteristics: 

• Extremely simple interface. Should be vastly simpler than doing it the non-appliance way. I.e. a Cisco router is vastly simpler than running routed on a UNIX box.
• A single purpose. The device must be dedicated to doing one thing, but doing it extremely well. Like the way a Cisco router is much better at doing routing than a UNIX box running routed. Or like the way a NetApp filer is much better at doing NFS file serving than a UNIX box running nfsd. You get the idea. By dramatically reducing the number of functions the device performs, you also dramatically reduce the amount of code that must be run on the device. (The original NetApp ONTAP OS was a single-threaded 16 bit OS with only a few 100K of lines of code.) This leads to the next feature of an appliance which is:
• Vastly reduced cost. The original NetApp filer was about a $5,000 device. An equivalent UNIX box used as an NFS file server ran around $50,000. Similar cost differences existed for Cisco routers vs. UNIX boxes as routers.
• Transformative technology. An appliance, if it is truly an appliance, becomes the obvious and natural way to do things. Within a very short period of time after introducing the router, Cisco controlled the router market. They completely displaced the previous way of doing routing. The same thing occurred in file serving with NetApp.

 By any reasonable measure, Oracle ExaData fails all of these tests:

• It has as complex an interface as any Oracle database server (which is to say it runs the most complex and expensive piece of software ever written for general purpose use). Certainly not appliance-like.
• An Oracle ExaData rack contains general purpose compute servers, which can be used to run basically anything you want. You can load any Oracle application on it certainly, and no-one would claim that an Oracle database server is an appliance!
• Oracle ExaData is manifestly more expensive than a normal, open-systems database server, and vastly more expensive (assuming intelligent management) than using VMware vSphere for virtualizing Oracle database servers.
• Oracle ExaData is possibly addictive in the Big Blue sense, but it is certainly not a transformative technology in the same way that a Cisco router, iPad, iPhone, or such is.

In terms of an analogy that works, I like to use cars. The two companies in the car business that manufacture appliance cars are Honda and Toyota. The Honda Civic is an appliance car, as is the Toyota Camry. Either one of these cars provides all of the appliance advantages:

• They have a radically simplified interface. Everything about these cars is designed to make them effortless to operate. Because they are so simple, they are also very reliable and efficient.
• They are single purpose vehicles. They get you from point a to point b. That's it. Nothing fancy.
• They are sold at a very reasonable cost, relative to non-appliance vehicles (such as BMW, or Mercedes for example).
• Once you have driven a Honda Civic or Toyota Camry, assuming you are an appliance driver (and there are a lot folks who are appliance drivers), these cars are completely addictive. You simply trade one in for the new model once the old one wears out (and they take a long, long time to wear out). I have known folks who have been driving these cars (in various model years) their entire lives. 

Using the car analogy, ExaData is definitely not a Honda or a Toyota. It is not even a BMW or a Mercedes. It is a Ferrari. It is a tricked out, high performance machine. It is very fast, no question. It is *&^% expensive though. And it is very, very complex and demanding to drive.

Oracle Licensing on VMware - no magic

Acknowledgements to Bart Sjerps for this content.

There seems to be a lot of confusion on licensing when customers consider running Oracle databases on VMware. Part of the confusion is caused by Oracle on purpose (classic FUD) by suggesting licensing is more expensive on VMware than on physical servers. The reality couldn't be more different - I strongly believe that many customers can actually *save* on database licenses by going virtual. But to understand how to achieve this, you need to know a few things - I hope I can clear this up in a short explanation. I will keep the discussion to Oracle database licenses and ignore application/middleware etc. for now.

License models

Customers typically license their basic database by one out of three options:

1. License by CPU (core) - the more CPU cores, the more licenses are needed. There is a processor core factor depending on the type of CPU and can be 0.25, 0.5, 0.75 or 1.0.
2. License by named user - the more named users, the more licenses are needed. The amount of CPU's is not important, neither the amount of total databases. Typically one license pack per 25 users.
3. Enterprise License - the customer negotiates a contract for the whole company and afterwards can deploy as many databases on as many servers/cpus as he wants.

If a customer uses 2 or 3, then it does not matter if they run virtual or physical. But there are also no license savings possible without re-negotiating their contracts. I don't want to go as far as suggesting to customers to change their license models so we leave this as-is for now.

In my experience, most enterprise customers use either cpu licensing or enterprise contracts. Some have different licensing methods for different business units. Oracle can be very creative in customer-specific contracts so expect to find a different situation for each individual customer.

But let's assume CPU licensing for the sake of this discussion.

Maintenance & support

Users typically buy the CPU licenses  but then have to pay maintenance for the time they use the licenses. Yearly maintenance cost is about 25% of license (list price). I have no information on typical discounts. I expect customers to get at least 50% discount off the price list (but only on licenses, not on maintenance AFAIK).

Database Edition and options

The plain database license comes in 3 versions (for servers):

1. Standard Edition One - Maximum 2 processors, no options allowed. Only used for testing and very small deployments
2. Standard Edition (SE) - Maximum 4 processors, no options allowed. Only used for smaller sizes and workloads (but stay tuned)
3. Enterprise Edition (EE) - No limitations and on top of EE, you can have many licensed features. Most customers will use this, at least for production databases

On top of the basic Database license, most customers use a set of options, each requiring additional licenses per CPU. The most common options are:

• Real Application Clusters (RAC) - allows many servers running the same database (active-active clustering) to allow scale out performance and high availability.
• Real Application Clusters One Node - same but one database can only run actively on one node. For high availability only.
• Active Data Guard - remote replication using log shipping. Note that standard Data Guard is free, but Active Data Guard allows the standby database to be opened for read-only purposes and offers some extra features.
• Partitioning - allows tables to be split up in smaller chunks. Absolutely required when running large databases and no downtime can be tolerated. Eases administration work and offers some performance benefits.
• Real Application Testing - allows workloads to be recorded and re-played on another database to do performance and functionality testing
• Advanced Compression - allows database blocks to be compressed - requiring less storage and boosting performance (in most cases).
• Diagnostics Pack / Tuning pack - provides automated reports. Oracle AWR (Advanced Workload Reports - a performance reporting tool) is part of Tuning Pack.

In my experience, nearly all customers have partitioning. Most customers have tuning/diagnostics pack. Some customers have RAC. Some customers have the other options. There are more options available but these are the most common.

Many customers have 3 or more options - sometimes the options cost more than the base database license - especially if they use RAC they will have most of the other options, too.

Running on a cluster

If a database runs on a cluster, then Oracle assumes the database can make use of any processor in the cluster. This is independent on what kind of cluster is used (so can be MSCS, HP MCSG, Vmware, Oracle RAC, etc).

This is basically the foundation for all FUD and confusion. For example, if you deploy a VMware farm (cluster) of 16 servers, and all virtual machines run all kinds of stuff (file/print, exchange, apps, etc etc) and only one tiny virtual machine in the corner, with only one virtual CPU runs a small Oracle database, you would expect only to pay for one CPU core - but Oracle's reasoning is that this tiny VM can be dynamically moved (VMotion) to all nodes in the cluster and on any processor. Therefore, all CPU's have to be fully licensed by Oracle. So in this case, running the single database on a (small) physical server would be cheaper than running on a VM in the farm.

Total cost of the stack

In a typical database server deployment, the cost of the database licensing is far greater than the cost of the hardware + OS licenses combined. I have no hard numbers but I assume the average DB license cost (plus options) is 10 times larger than the cost of the server + OS.

So a $5,000 server would typically require $50,000 on licenses. Then because maintenance is 25% yearly, the total cost of licenses over a 3 to 5 year period is even higher - so for a 5 year TCO the total license cost might be $75,000 (assumption - could also be closer to $100,000 - and no, I didn't make a mistake with an extra zero, Oracle *really* is this expensive).

Utilization

It is very hard to size a typical Oracle database based application. There are no good methods or calculations to figure out how much CPU power, disk I/O and memory is needed to run a given app. So historically, project teams size their database servers for peak loads, and because they cannot predict how big the peak load is, they double the resources "just in case". The end result is that most database servers are way oversized in terms of CPU and memory.

Most physical deployed database servers will average on about 10-15% CPU load (or less). However, they will peak to higher loads at certain times, such as monday morning when many users log in, or when month/quarter/year-end batch processing is started, etc.

Then, the utilization numbers can be influenced by other tasks of the processors. Some common causes of "artificially high" CPU loads on database servers:

• CPU is involved in storage mirroring (i.e. Host Level Mirroring - using Oracel ASM or a Unix volume manager)
• CPU is involved in file transfers over the IP network
• Backup (non-serverless, using CPU, Network and I/O bandwidth)
• Customers run the application server on the same machine driving up CPU load - This can drive up CPU load from 10% to 90% or more !!
• Same for Middleware and Enterprise Service Buses (Think Oracle BEA, IBM Websphere, SAP Netweaver, etc)
• A  bunch of monitoring/management agents burn CPU cycles (Tivoli, BMC, HP Openview, CA, etc). Each agent maybe consuming 1% but add it up and you have another 5-10% overhead.
• Administrators generate database dumps / exports and run their own reports, scripts and tools. They run ad-hoc queries as well that should not be on production.
• Poorly tuned database servers cause paging and other CPU overhead - hard to diagnose but driving up CPU and I/O significantly.
• Database admin tasks (table reorganizations, (re)building indexes, converting tablespaces, ...)
• And so on...

All of these cause the processors, expensively licensed for database processing, to do other stuff.

So if a server is running at 15% utilization, then the utilization caused by the database workload itself might only be 10% and the rest caused by other stuff (whether needed or not).

Needless to say that Oracle likes customers to use their expensive licensed CPU's for other tasks because it forces them to buy additional CPUs sooner and therefore drive their license revenues.

Isn't life great for an Oracle rep? ;-)

Number of databases

Most customers run many databases. For the average enterprise customer that I visit, 100+ databases is a normal number. A big global that I visited runs 3000+ Oracle databases worldwide (and this is only the scope of this specific project team). Imagine the cost of licensing all these databases on all individual servers...

Why so many? Well, customers do not like to share multiple applications on one database (and often this is not even supported). So if you run SAP ERP, Oracle JD Edwards, your own banking app and a few others, they all require their own production database.

For each production database, you might find an acceptance environment, test system, development server, maybe a staging area to load data into the data warehouse, maybe a firefighting environment, a standby for D/R, a training system and so on. Customers will rarely share production environments on the same server (unless virtualized or at least with workload management segregation). Sometimes they share a few databases for non-prod on a server. So for, say, 100 databases, the average customer runs between 30 and 50 (physical) servers.

Power of big numbers

It does not require rocket science to understand that many of these databases do not require peak performance at the same time. A development system typically drives workload during daytime (when developers are coding new application features). A data warehouse runs queries during the day and loads in the evening. For a production system it depends on the business process. An acceptance system might sit idle for weeks and then suddenly peak for a few days preparing for a new version deployment into the live production system. And so on.

So what if you could share resources across databases - without influencing code levels, security, stability and so on?

If that would be possible - you would not size for "peak load times two" anymore. You would size for what you expect and assume an average utilization of, say, 70% over the whole landscape. If one database needs extra horsepower, there is enough available in the landscape.

How much license cost would you save by bringing down the number of CPU's so that utilization goes up from 10% to 70%?

What would be the effect on power, cooling, floor space, hardware investments, time-to-market?

What would be the business advantage of not limiting production performance of a single server, by whatever was sized during initial deployment? Risk avoidance?

What would be the business advantage of solving future performance issues by just adding the latest and greatest Intel server in the cluster and Vmotion the troubled database over?

Wasn't this exactly why we started server virtualization in the first place about 8 years ago? And why EMC aquired VMware?

Wouldn't you think the average Oracle sales rep is scared to death when his customer starts considering to run his databases on a virtual (cloud) platform? Would it make sense for him to drive his customers mad with FUD around licensing, support issues and whatever he can think of to prevent his customers going this way? Even threatening to drop all support if they continue to go in that direction?

If Oracle is scared of losing license revenue, wouldn't you think there is a huge potential for savings for our customers here?

The journey to the private database cloud

So how should we deal with this?

A few starting points:

• Oracle supports VMware. Period. Any other claim of Oracle reps can be taken with a grain of salt (to be more specific: it's nonsense).
• Oracle does NOT certify VMware. Then again, Oracle does not certify anything except their own hard- and software. But IMO, support is all you need and the discussion around certification leads nowhere.
• Oracle might ask the customer to recreate issues on a physical server if they suspect problems with the hypervisor. Isn't it great that we can do this easily with Replication Manager? ;-)
• Oracle only supports Oracle RAC on VMware for one specific version (11.2.0.2). Any other version with RAC is not recommended on VMware because of support issues. Expected to change in the future.
• Both EMC and VMware offer additional support guarantees for customers deploying Oracle on Vmware. So where Oracle pulls back, EMC and VMware will fix any issue anyway.
• Performance is no longer an issue. With Vsphere 5, a single virtual machine can have 32 virtual processors, 1 TB ram and drive 1 million iops. Only the most demanding workloads would not fit in this footprint. But with customers running hundreds of databases, maybe we should start with the 95% + that DO fit and make significant savings there. By the time we're done, VMware will have Vsphere 6 and who knows what happens then.

How to get around the licensing issue

As I said, Oracle requires licenses for all servers in a cluster. So how do you limit the number of licenses? By deploying an Oracle-only VMware cluster. Only run Oracle databases here. No apps, no middleware, no fileservers, and try to move everything off that does not relate to database processing. No host replication, no storage mirroring, etc.

Say you have a legacy environment with 10 servers, each with 16 cores, so you have 160 cores licensed with oracle EE and a bunch of options. Average CPU load is 15% but let's assume 20% to be conservative.

I claim that a single VMware cluster with 3 servers each with 32 cores will easily do the job. Now we have 3 * 32 = 96 cores to be licensed. 96/160 = 0.6 = 60% so we saved 40% on licensing right away. Probably the average CPU load on the whole cluster will still be much less than 70% so we can gradually add a bunch more databases until we average out on 70%.

If the old system was not running Intel x86 but SPARC, PA-RISC or POWER cpu's then the processor factor was probably 1.0 or 0.75. Intel has 0.5. So for 96 cores (Intel) you would need to pay 48 full licenses. Another 33% savings.

The savings of 40% on licensing will easily justify an investment of a nice new EMC storage infrastructure with EFDs, FAST-VP and all other goodies. Do you think the customer will push us hard for a $0.01 lower GB price competing HDS or Netapp if we just saved them millions in Oracle licenses?

But the story does not end here.

Additional savings

Let's assume the customer needed high availability and scale-out performance and was running Oracle RAC. RAC is the most expensive licensed option and you need at least two for a two-node cluster. But VMware allows for HA (High Availaiblity clustering) as well. Using VMware HA instead of RAC, you would have to fail-over and recover the database in case of an outage - if the customer cannot tolerate this then he needs to stick with RAC (only for mission critical databases!). But most customers can live with 5 minutes of downtime in case a server CPU fails and in that case, replacing RAC with VMware HA can save them another big bunch of dollars.

Let's assume that with virtualization you justified the investment in a nice EMC infrastructure with Flash drives to replace the competitive gear. Now the Oracle cluster is no longer limited by storage I/O's and can drive more workload out of the same 3 VMware servers in the cluster. But you can also replace host mirroring (where applicable). You can implement snapshot backups to get the I/O load away from the production servers. You removed the middleware and apps stuff from the database servers - reducing CPU utilization and allowing even more headroom for DB consolidation - all without buying extra licenses from Oracle.

You have a customer who wants even more?

What if they create TWO database clusters for VMware? One for production (running Oracle Enterprise Edition (EE) with all the options they need) and one for Non-prod (running Oracle Standard Edition (SE) without options - good enough for test/dev and smaller, non-mission critical workloads). I bet the number of non-prod databases will be much more than prod. By removing the expensive options AND moving from Enterprise to Standard Edition, you saved another ton of money on Oracle licensing as SE is much cheaper than EE. But be aware - the devil is in the details and using Standard Edition is not for the faint-of-heart (for example, you could no longer clone a partitioned database to a SE enabled server because of the missing license and functionality). Still if the customer is keen on saving as much as possible, then this might be the final silver bullet...

Do they run a huge Enterprise Data warehouse? Carefully find out if they have troubles with it and see if you can position Greenplum - saving another bag of money and speeding up their BI queries. But be careful, in an Oracle-religious shop it might backfire on you...

Reality Check

I had this discussion already with a few enterprise customers. And found that although the story is easy in theory, the reality is different. If a customer already has the 160 CPU licenses purchased from Oracle, then the Oracle rep will not happily give a money-back in return of the shelfware licenses. So in that case the customer can only save on maintenance and support. But having enough licenses on the shelf, he would not have to purchase any more for the next 5 to 10 years. So talk cost avoidance instead of immediate savings. And again, if they are licensed by user or have a site license, then saving on licenses will be a tough discussion. Still, the savings on power/cooling/hardware/floorspace would still be significant enough to proceed anyway.

And don't forget the other benefits of private cloud of which we all know how to position: they are no different for Oracle than for other business applications.

Final thought

For this to work you need a customer that is willing to work with you and be open on how they negociated with Oracle, and a team of DB engineers to work with you to make it happen. If internal politics cause significant roadblocks then you will get nowhere.

It's not an easy sell but the rewards can be massive. We're only just starting to figure out how to convince customers and drive this approach. Feedback welcome and let me know if you need support.

Resources

The online Everything Oracle at EMC community has lots of information on this subject. See in particular this presentation which I co-presented (with Sam Lucido) at this year's VMworld.

Landing page with Oracle 's price list: http://www.oracle.com/us/corporate/pricing/price-lists/index.html

Download "US Oracle Technology Commercial Price List" for the database license document. Read the fine print because it's not always as simple as it seems.

Processor Core Factor information:http://www.oracle.com/us/corporate/contracts/processor-core-factor-table-070634.pdf

 

Darryl Smith's Oracle RAC Recent Blog Post

EMC IT's Darryl Smith recently issued an outstanding blog post on our ECN community, the subject of which was: Is Oracle RAC Becoming More of a Corner Case? I thought I would add a few thoughts to Darry's blog post.

I have been saying for a while that most Oracle databases do not need the level of uptime and fault tolerance that RAC provides, so Darryl and I are certainly thinking along the same lines.

I think that the value proposition for vSphere and NFS are very similar. Given that I have spent the bulk of my career pushing NFS and NAS for Oracle database storage, the synergy is obvious at least to me.

Both technologies are about having a "good enough" infrastructure for an Oracle database which, while certainly important to the business, is not the back-end for an online catalog, or an online securities trading app.

For databases like that, I would recommend neither vSphere nor NFS. But the vast, vast majority of databases running Oracle do not fall into this category.

In the case of NFS, for years I made the statement that I believe that 90% of all Oracle databases running in datacenters all of the world could be run over an NFS mount with absolutely no change in performance, reliability, or user experience. (There would, on average, be a big reduction in cost and improvement in manageability, though.)

vSphere is exactly the same. For anything other than the most barn-burning performance, with absolutely the highest standards of fault tolerance, vSphere works just fine. It provides a very high level of reliability, a few minutes a year of downtime, at a vast reduction in cost and complexity compared to RAC.

Because the value propositions are so similar, I believe that the combination of NFS and vSphere is going to become increasingly popular. We'll certainly see how it turns out.

 

Oracle OpenWorld 2011 Technical Sessions: Part 1

This begins a series of blog posts on the subject of technical sessions that EMC presented at OOW2011. To begin with, we will examine the session that I co-presented with Kevin Jernigan entitled Clone Oracle Databases Online in Seconds with Oracle Clonedb and DirectNFS. The presentation for this session can be found here.

It may sound strange given EMC's reputation and history, but EMC has a strong partnership with Oracle in the area of NAS. We began working with Oracle on the Direct NFS client ("dNFS") way back in 2007, when dNFS was introduced as a major new feature in Oracle Database 11g Release 1. At that time, EMC, was a co-presenter (together with Oracle) at Oracle OpenWorld 2007 on this subject.

The goals of dNFS were simple, and well defined:

• Improve performance (in terms of latency and throughput) of NFS-mounted Oracle database I/O
• Reduce CPU cost of NFS-mounted Oracle database I/O
• Improve network port scalability and failover of NFS-mounted Oracle database I/O
• Simplify administration of NFS in terms of both network port scaling and mount point parameters
• Make administration of NFS uniform across all platforms

dNFS succeeds widely at all of these. dNFS dramatically improves latency of network I/O from Oracle by eliminating most context switches and making the code path to the disk much shorter. dNFS also provides better port scaling than kernel NFS, with much simpler administration. No fussy ether channel network switch configuration is required. All of the port scaling and port failover is provided within the Oracle environment.

 

dNFS also made administration completely uniform across all platforms. Amusingly, Windows is included! NFS now works on Windows, at least with an Oracle database.

In September 2010, Oracle announced that dNFS would be improved in Oracle Database 11g Release 2. One major improvement is the addition of dNFS clonedb, a thinly-provisioned, rapid database replication feature. This feature also works very well with storage-based replication.

 

The basis for dNFS clonedb is a database copy. This copy can be a backup, a storage-based snapshot or clone, or an operating system copy. (Of course, EMC likes to leverage our storage-based snaps and clones.)

 

Once a copy exists, it can be used to create a clonedb instance. The steps to do this are contained in My Oracle Support article 1210656.1 . Effectively, this creates a read / write virtual database which takes up minimal space, is created almost instantly, and contains only the space required to store any changes to the database. Given that storage-based snapshots are also space and time efficient (that is, they take up very little space, and can be created very quickly) there is a great deal of synergy between these technologies.

 

EMC did some performance testing with dNFS clonedb. The network diagram for the testbed is here:

First, we established a baseline in terms of performance. We ran an OLTP workload against the production database with no additional operations. This produced the following:

Notice the perfectly clean scaling of this performance chart. We then tested the performance of creating a snapshot to serve as the source for the clonedb database. This produced:

Note the slight response time hit when the snapshot was taken. However, transactional throughput was not affected. Basically, this is at most a minimal performance hit. Finally we tested performance while creating clonedb database instances from the storage snapshot. This produced:

Note that there was no performance hit during clonedb creation at all. One additional test was performed. We measured the storage space occupied by the clonedb when it was created. A 10 TB database was used as the source. The total space occupied by the clonedb was only 7 MB.

See the link above for the full presentation of this technical session. Further blog posts in this series will contain summaries of other EMC technical sessions at OOW 2011.

Thoughts on Oracle OpenWorld 2011 Keynotes

I attended Oracle OpenWorld 2011 as usual this year, at which I co-presented a technical session with Kevin Jernigan on the subject of Direct NFS clonedb. Since I had a full conference pass, I was able to attend many of the keynotes at this event.

I did not get to attend the Sunday Larry keynote, although I understand that it was pretty terrible. I did attend the Wednesday Larry keynote, and can tell you this: As a long-term Larry watcher (I have attended every OOW since 1998) it was hands down the worst Larry keynote I have ever seen.

Perhaps because Larry had just lost his best friend (Steve Jobs died of cancer the day of this keynote), he was off his game. That's the only reasonable explanation I have for such a spectacular failure of such a precious and expensive opportunity.

Larry's keynote consisted largely of a 20 minute-plus long demo of Fusion Applications, which while interesting in itself, was excrutiatingly dull, and definitely would have been much better if handled by someone other than Larry.

What Larry is great at (and what was largely lacking in his keynote) is the flamboyant, extravagant, and provocative way that he baits his competitors and makes outlandish claims concerning his own products' performance. He did a bit of sniping at (SalesForce.com Chairman and CEO) Marc Benioff. Aside from that, nothing.

The other Oracle keynotes were not much better. This was an almost content-free OOW for me. The ExaData and ExaLogic stuff was more of the same from last year. The big product launch was of course Fusion Applications, but that is just software. There was no big splash on the hardware side.

The best keynotes by far were Joe Tucci and John Chambers. Both provided a lot of content, much of which was competitive to Oracle, interestingly. Cisco is certainly competing with ExaData in the server market and EMC competes with Oracle in storage, virtualization and datawarehousing software. All of this was discussed extensively during these keynotes. Joe even said the "v" word (VMware) during his keynote, and Pat further elaborated on this subject during his follow on to Joe's talk. Pat also included a long demo of vCenter which was assisted by EMC's own Chad Sakac.

Chambers talk was very compelling to me. His vision for a new platform in the post-PC age was a serious challenge to both Microsoft and Apple in their ecosystems. I am a bit skeptical that Cisco can successfully compete with those vendors in their respective spaces, though. Microsoft owns the business productivity space, and Apple has a serious stake in the home and home office space. Cisco will need to penetrate both of these in order to fulfill Chamber's vision. We'll see.

I thought OOW was about Oracle. This year, not so much. This year, the interesting stuff at OOW was from other vendors. Score one for EMC and Cisco, and score zero for Oracle this year.

High Performance Database Cloning with Oracle Direct NFS Client clonedb

For those who attended EMCWorld in April, you are probably aware of the joint presentation that I made with Kevin Jernigan of Oracle. This session was sponsored by Oracle, and showcased the joint solution that EMC and Oracle have created together around the use of Oracle Direct NFS Client (dNFS) clonedb to create thinly provisioned, on-demand, lightweight clones of a running production Oracle database. Oracle and EMC are also jointly writing a white paper covering this solution, which will be published imminently on EMC's Powerlink website. I will advise you on this blog when this white paper is available.

In the meantime, the purpose of this post is to provide a summary of this solution, and give an overview of the results of the joint EMC / Oracle testing.

First a bit of history. Although EMC does not have the reputation in NAS storage for Oracle databases that some other vendors have, we have done a lot of work in this area, and I believe we have captured leadership.

EMC has been working on dNFS with Oracle since it went into beta in 2007 as part of Oracle Database 11g Release 1. We made our first joint presentation with Oracle on dNFS on EMC storage at Oracle OpenWorld in 2007.

We began work on a scalable performance solution in 2010, demonstrating performance within 5% of ASM over FC on equivalent server and storage hardware. This solution was also jointly published with Oracle.

Finally in this year, we have produced the dNFS clonedb solution which is the subject of this post, and which was presented jointly by Oracle and EMC and EMCWorld in April of this year. We also hope to jointly present this solution at Oracle OpenWorld 2011. More on this later.

Now some background. First on NFS. NFS was created by Sun in 1985. It is an RFC-based UNIX protocol based upon TCP/IP, and a sibling of FTP, SSH, POP, and so forth. NFS was undoubtedly the first widely deployed method for file sharing in the industry.

NFS and NAS are equivalent terms within the database storage industry. NAS simply refers to the storage of databases on a NAS array over NFS using an IP storage network. NFS became popular for database storage starting in the mid-1990s. I was personally involved in that movement during the period that I was working for NetApp. See my earlier posts in this blog for details on that.

NFS provided the following benefits relative to traditional SAN storage over FC:

• Cheap, low TCO
• Simple and fast to deploy, because of the underlying network technology, i.e. TCP/IP over Ethernet
• Easy storage virtualization
• Easy shared file system which supported grid computing

The challenges of NFS were:

• Relatively low performance compared to FC. This is because the I/O algorithms within NFS were optimized for file server I/O, i.e. a large number of lightweight processes using relatively low level I/O against a very large number of files. Database I/O is the exact opposite: A small number of very heavyweight processes doing a lot of high level I/O against a fairly small number of files.
• High CPU utilization of the protocol
• Management complexity across platforms. Each platform had its own wrinkles in terms of things like mount point parameters
• Poor scalability across Ethernet ports, requiring the use of complex, CPU intense port trunking at the Linux (or UNIX) kernel level

In response to these challenges, in 2007, Oracle introduced dNFS as part of Oracle Database 11g Release 1. dNFS was simply an implementation of the NFS protocol inside the Oracle database kernel. The benefits provided by dNFS were:

• Improved performance by tuning the protocol to match typical database I/O patterns
• Reduced CPU utilization
• Uniform management interface across all platforms (including, ironically, Microsoft Windows)
• Vastly superior transparent port scaling by implementing the ability to pool Ethernet ports within dNFS, rather than within the OS layer.

The results, as demonstrated by the testing performed by both Oracle and EMC have been exceptional: dNFS provides nearly equivalent performance to ASM over FC, while allowing the customer to use IP storage. This provides lower cost, better TCO, and simpler management. dNFS has been a wildly successful product for Oracle as a result.

Now to dNFS clonedb. In 2010, Oracle introduced dNFS clonedb as part of Oracle Database 11g Release 2. The idea behind dNFS clonedb is to create a feature which allows you to instantly clone a running Oracle production database which is mounted over dNFS. The clone is based upon a copy of the production database. This copy can be a storage-layer virtual copy, however, including a snapshots. Using the combination of this copy, plus the running production database, you can create an unlimited number of clones, each of which takes up minimal space, and has minimal performance impact on the production database.

Thus, the benefits of dNFS clonedb are:

• Clones are created instantly
• You can have an unlimited number of clones
• Clones take up minimal space
• No performance impact on the production database
• Performance of I/O against the clone is comparable to the production database

The objectives of the solution were simply to prove these benefits.

The solution has two major components:

• RAC production database with single instance dNFS clonedb (RAC testbed)
• Both production database and dNFS clonedb as single instance (SI testbed)

Two sets of testing were required because we wanted to test the impact of creating dNFS clonedb databases against a highly-scalable RAC implementation. Most of the testing was in this environment, so we will start with that one. However, we also wanted to compare the performance of the dNFS clonedb database itself to a normal dNFS mounted database. And since the dNFS clonedb database was running on a modest single-instance Oracle database server, this required for us to perform an additional performance test against a production server on the same hardware. This enabled us to directly compare the performance of dNFS clonedb against a normal production database.

Let's start with the testing of the RAC component. The network diagram for this component was as follows:

As shown in the diagram, the major features of the RAC environment are:

• Oracle Database (and RAC) 11g Release 2, which includes dNFS and clonedb
• EMC NS-960 unified storage array
• EMC Replication Manager (RM) which is responsible for managing the process of creating snapshots (using EMC Celerra SnapSure checkpoint) of the running Oracle production database

The first step of the testing was to create a baseline of normal performance on the production RAC database. This was done using an industry-standard OLTP benchmark. This produced the following result:

The next step was to test the performance impact of creating snapshots using EMC Celerra SnapSure checkpoint and RM. RM takes the database into hot backup mode while the snapshot is being created, and this results in a slight response time performance hit. However, TPS is not affected, and the response time effect is very short-lived (only during the brief period when the database is in hot backup). Here is that result:

And finally, on the last test in the RAC component, we created two clone databases using dNFS clonedb. These operations were run while the production database was under load using the OLTP performance benchmark, of course. The effect of these operations on performance was minuscule: We simply could not find any effect at all. The run was identical to the baseline for all practical purposes. We concluded that dNFS clonedb has no perceptible impact on the production database. Here is that result:

As you can see, as I said, this is basically identical to the baseline.

Finally, we need to add the single instance testing to show the performance impact of clonedb on the clone database itself. Here is the network diagram for that testing:

This is identical to the RAC testbed, with the exception that the production database is on a single instance server, instead of a RAC cluster. Also, the hardware configuration used for the production database was identical to that used for the clone database. This allowed us to run a baseline on the production system, and then compare that to the a performance run against the clone database. This produced the following result:

At the peak TPS, this result produced the following performance:

    clonedb:            400 TPS
    Non-clonedb:     445 TPS
    Difference:        10%

Thus, the clonedb feature under an OLTP workload is within about 10% of a normal dNFS mounted database, which I consider to be quite respectable.

We also timed the clonedb creation and snapshot creation operations. They were very brief. The snapshot creation operation, including a complete RM run with hot backup, mounting, and so forth, took about 7 minutes. Creating a clonedb database only took about 10 seconds.

The final benefit we tested was space. At creation, the clonedb database takes up virtually no space, as the following chart indicates:

Thus, at creation, a clonedb of an 11 TB production database took up only 7.4 MB of space. This is slightly misleading though. As edits are made to the clonedb database, it will begin to occupy space. The space overhead of a clonedb database can actually be easily determined as the number of database blocks which are different between the clonedb and the production database. Nonetheless, the typical clonedb database can be expected to take up far less space than a physical copy of the production database.

I believe that dNFS clonedb is an incredibly attractive and powerful addition to Oracle's already feature-rich database offering. I would recommend anyone interested in exploring NAS storage for Oracle databases to give dNFS a strong look, and especially to consider clonedb for creating clones of production databases.

VMworld 2010 Session Content Part 2 - Internal vs. External Cloud

Per my previous post, this is part 2 of a series of posts to provide the content of my recent VMworld technical session.

As I said in my previous post, the impending data explosion will produce huge challenges for the Oracle database community, in that the amount of scaling of Oracle database environments will an order of magnitude greater than the overall data explosion. My unofficial estimate is approximately a 200X increase in data volume managed by Oracle in the next 10 years (as opposed to about 44X overall). This creates the challenge of figuring out how to scale Oracle database environments in order to handle all of that data (as well as the transactional I/O that accompanies it).

In my view, there are two competing ways of scaling an IT workload presently, from a strictly structural standpoint: The external cloud and the internal cloud. (I will further break down the options on the internal cloud in my next post.)

The following diagram gives some insight in what I am talking about here:

 
Those of you who know me well know how fond I am of this type of diagram: The so-called "magic" diagram. Here the vertical dimension represents virtual vs. physical and the horizontal represents internal vs. external (from the perspective of the customer data center). A typical multi-layered application environment is shown with three layers: Web, App and Database. As is typical with most environments, the entire workload starts out in the customer's data center. Further, there is ratio of 9:3:1 for Web vs. App vs. Database. This is somewhat contrived, but fairly typical and real-world in my opinion. Thus, the initial workload when originally deployed looks like this:

For a while, the capacity of internal data center is able to handle the growth in this workload. I call this the period of normal growth. At the end of this period, the web server farm is beginning to exceed the capacity of the traditional data center. This looks like this:

At this point, the customer has a decision: They can either move the web server farm into the cloud, or they can move it out to a traditional external service provider (i.e. co-host location). Perhaps a progressive or farsighted customer would go ahead and move into the cloud. But most folks in my experience have not done so. Instead, they go through a period of scaling where the web server farm is located on a service provider's data center, and then continue to scale the rest of the workload internally. This enables the second period which I call accelerated growth. At the end of this period, the workload looks like this:

Growth has now become somewhat unmanageable. You can see that the co-location model is breaking down. Also, the capacity of the internal data center to absorb the App server farm is now being stressed. Again, the customer has to make some hard decisions. The easiest decision is to move the Web layer into the external cloud. This is easy, cost effective and very mainstream. The App server farm may be either moved into an external or internal cloud, or possibly moved out to the co-location facility. We will assume the latter.

At this point the customer begins the final period of growth, which I call explosive growth. The external cloud provides virtually infinite growth capacity for the Web server layer, but the co-location in an external service provider can now no longer handle the demands of the App server layer. And, finally, the Database server layer is now exceeding the capacity of the internal data center. At this point, the workload looks like this:

Another doubling of the workload, and the customer will be in big trouble. Hard decisions must be made. It is likely at this point that the customer will move the App server layer into the external cloud. Doing so is now fairly mainstream. The decision remains of what to do with the Database server layer.

Understand that I have personally engaged in these discussions with many customers. I think I know the mind of the DBA (as I have been one for many years). Most DBAs when confronted with this choice will make the following calculation:

Am I going to put my precious database, my business's crown jewels, which contain the source data of the business, our very lifeblood, into the hands of an external cloud provider, in what is certainly a very unstable and emerging technology space?

The answer for most DBAs is: No way! Thus, the decision is typically that the scaling of the database layer will be handled as an internal cloud. Many large customers are today launching exactly this type of project which goes by many names, but which is ultimately the idea of creating a Database as a Service (DBaaS) offering which is managed entirely by internal IT. Thus, the final evolution of our example looks like this:

The essence of the internal database cloud is the idea that we divorce the physical database server from any particular project. Rather, database access is provided as a utility service at a cost. The customers (internal IT projects in this case) contract with IT to have this provided. The billing may be on physical storage, transactional I/O, or some other measurement. But the effect is the same. The challenge for DBAs, system administrators, and storage administrators is to provide this service cost-effectively and reliably. But the payoff is huge. Only by providing this type of offering can the customer have any hope of scaling the workload in a period of explosive growth.

My next post will provide a breakdown of the approaches to creating an internal Oracle database cloud, and the choices that customers are making in that regard.

Finally, please remember that I will be at Oracle OpenWorld which is only a couple of weeks away. Please join me in the EMC booth, and I hope to see you there.