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Jeremy Schneider

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Jeremy Schneider
Updated: 3 hours 7 min ago

OSP #3a: Build a Standard Cluster Platform

Thu, 2014-04-17 05:15

This is the fifth article in a series called Operationally Scalable Practices. The first article gives an introduction and the second article contains a general overview. In short, this series suggests a comprehensive and cogent blueprint to best position organizations and DBAs for growth.

We’ve looked in some depth at the process of defining a standard platform with an eye toward Oracle database use cases. Before moving on, it would be worthwhile to briefly touch on clustering.

Most organizations should hold off as long as possible before bringing clusters into their infrastructure. Clusters introduce a very significant new level of complexity. They will immediately drive some very expensive training and/or hiring demands – in addition to the already-expensive software licenses and maintenance fees. There will also be new development and engineering needed – perhaps even within application code itself – to support running your apps on clusters. In some industries, clusters have been very well marketed and many small-to-medium companies have made premature deployments. (Admittedly, my advice to hold off is partly a reaction to this.)

When Clustering is Right

Nonetheless there definitely comes a point where clustering is the right move. There are four basic goals that drive cluster adoption:

  1. Parallel or distributed processing
  2. Fault tolerance
  3. Incremental growth
  4. Pooled resources for better utilization

I want to point out immediately that RAC is just one way of many ways to do clustering. Clustering can be done at many tiers (platform, database, application) and if you define it loosely then even an oracle database can be clustered in a number of ways.

Distributed Processing

Stop for a moment and re-read the list of goals above. If you wanted to design a system to meet these goals, what technology would you use? I already suggested clusters – but that might not have been what came to your mind first. How about grid computing? I once worked with some researchers in Illinois who wrote programs to simulate protein folding and DNS sequencing. They used the Illinois BioGrid – composed of servers and clusters managed independently by three different universities across the state. How about cloud computing? The Obama Campaign in 2008 used EC2 to build their volunteer logistics and coordination platforms to dramatically scale up and down very rapidly on demand. According to the book In Search of Clusters by Gregory Pfister, these four reasons are the main drivers for clustering – but if they also apply to grids and clouds then then what’s the difference? Doesn’t it all accomplish the same thing?

In fact the exact definition of “clustering” can be a little vague and there is a lot of overlap between clouds, grids, clusters – and simple groups of servers with strong & mature standards. In some cases these terms might be more interchangeable than you would expect. Nonetheless there are some general conventions. Here is what I have observed:

CLUSTER Old term, most strongly implies shared hardware resources of some kind, tight coupling and physical proximity of servers, and treatment of the group as a single unit for execution of tasks. While some level of single system image is presented to clients, each server may be individually administered and strong standards are desirable but not always implied. GRID Medium-aged term, implies looser coupling of servers, geographic dispersion, and perhaps cross-organizational ownership and administration. There will not be grid-wide standards for node configuration; individual nodes may be independently administered. The grid may be composed of multiple clusters. Strong standards do exist at a high level for management of jobs and inter-node communication.

Or, alternatively, the term “grid” may more loosely imply a group of servers where nodes/resources and jobs/services can easily be relocated as workload varies. CLOUD New term, implies service-based abstraction, virtualization and automation. It is extremely standardized with a bias toward enforcement through automation rather than policy. Servers are generally single-organization however service consumers are often external. Related to the term “utility computing” or the “as a service” terms (Software/SaaS, Platform/PaaS, Database/DaaS, Infrastructure/IaaS).

Or, alternatively, may (like “grid”) more loosely imply a group of servers where nodes/resources and jobs/services can easily be relocated as workload varies. Google Trends for Computers and Electronics Category

Google Trends for Computers and Electronics Category

These days, the distributed processing field is a very exciting place because the technology is advancing rapidly on all fronts. Traditional relational databases are dealing with increasingly massive data volumes, and big data technology combined with pay-as-you-go cloud platforms and mature automation toolkits have given bootstrapped startups unforeseen access to extremely large-scale data processing.

Building for Distributed Processing

Your business probably does not have big data. But the business case for some level of distributed processing will probably find you eventually. As I pointed out before, the standards and driving principles at very large organizations can benefit your commodity servers right now and eliminate many growing pains down the road.

In the second half of this article I will take a look at how this specifically applies to clustered Oracle databases. But I’m curious, are your server build standards ready for distributed processing? Could they accommodate clustering, grids or clouds? What kinds of standards do you think are most important to be ready for distributed processing?

Chicago Oracle User Community Restart

Mon, 2014-03-24 12:47

Chicago is the third largest city in the United States. There are probably more professional Oracle users here than most other areas in the country – and yet for many years now there hasn’t been a cohesive user group.

But right now there’s an opportunity for change. If the professional community of Chicago Oracle users steps up to the plate.

Chicago Oracle User Group

First, the Chicago Oracle User Group has just elected a new president. Alfredo Abate is bringing a level of enthusiasm and energy to the position which we’ve been missing for a long time. He’s trying to figure out how to restart the COUG and re-engage the professional community here – but he needs input and assistance from you! If you’re an administrator or developer anywhere near Chicago and you have Oracle software anywhere in your company, then please help Alfredo get the user group going! Here are a few specific things you can do:

  1. Send Alfredo an email saying congrats and offering suggestions for the COUG. You can find him on LinkedIn or the COUG site below.
  2. Join the LinkedIn group that Alfredo set up for the COUG.
  3. Sign up for a free account at the COUG site: chicago.oracle.ioug.org
  4. Complete the survey at the COUG website (must sign up for free account, then look for “survey” link in the top navigation bar). This will help Alfredo think about planning the next event.
Lunch Huddles

A few years ago, I was part of a group of Oracle database users from different companies in Chicago who started hanging out regularly for lunches downtown. It was never a big event but it was a lot of fun to get together and catch up regularly. However I stopped organizing the lunches after a job change back into travel consulting and the birth of our daughter. I live on the north side of the city, I worked from home when I wasn’t traveling, and I wasn’t able to make trips downtown anymore.

Ever since, I’ve missed hanging out with friends downtown and I’ve always wanted to do these group lunches again. Besides the fact that I really enjoy catching up with people, I think that face-to-face meetups really help strengthen our sense of community as a whole in Chicago.

So – after far too long – I started the lunches again last week.
Oracle DB Lunch Downtown

Oracle DB Lunch Downtown

But it’s improved – there are now lunches happening all over ChicagoLand!

Tomorrow: Deerfield
This wednesday: Des Plaines
Next week wednesday: Downtown

Coming soon: Naperville?

Please join us for a lunch sometime! I promise you’ll find it to be both beneficial and fun! And also, please join the group on meetup.com – then you’ll get reminders about upcoming lunches in Chicago.

Spread the Word

Even if you don’t live in Chicago, you can help me out with this – send a brief tweet or quick email to any Oracle professionals you know around Chicago and direct them to this blog post. I hope to see some new life in the Oracle professional community here. It won’t happen by accident.

Command Line Attachment to Oracle Support Service Request

Fri, 2014-02-07 13:55

For those who haven’t looked at this in awhile: these days, it’s dirt simple to attach a file to your SR directly from the server command line.

curl –T /path/to/attachment.tgz 
     –u "your.oracle.support.login@domain.com" 
     "https://transport.oracle.com/upload/issue/0-0000000000/"

Or to use a proxy server,

curl –T /path/to/attachment.tgz
     –u "your.oracle.support.login@domain.com"
     "https://transport.oracle.com/upload/issue/0-0000000000/"
     -px proxyserver:port
     -U proxyuser

There is lots of info on MOS (really old people call it metalink); doc 1547088.2 is a good place to start. There are some other ways to do this too. But really you can skip all that, you just need the single line above!

OEM CLI Commands for Bulk Property Changes

Tue, 2014-01-14 14:05

This will be a brief post, mostly so I can save this command somewhere besides the bash_history file on my OEM server. It may prove useful to a few others too… it has been absolutely essential for me on several occasions! (I was just using it again recently which reminded me to stick it in this blog post.) This is how you can make bulk property changes to a large group of targets in OEM:

(oracle)$ emcli login -username=jeremy
(oracle)$ emcli get_targets -noheader -script | sed \
  's/Metric Collection Error/MCE/;s/Under Blackout/Blackout/;s/Status Pending/Pending/' >targets

(oracle)$ less targets
(oracle)$ awk '{print$4" "$5" "$6" "$7" "$8"~"$3"~Department~default"}' targets >inp

  or... awk '{print$4" "$5" "$6" "$7" "$8"~"$3"~Line of Business~test"}' targets >inp
  or... awk '{print$4" "$5" "$6" "$7" "$8"~"$3"~Location~chicago"}' targets >inp
  or... awk '{print$4" "$5" "$6" "$7" "$8"~"$3"~LifeCycle Status~Production"}' targets >inp

(oracle)$ less inp
(oracle)$ emcli set_target_property_value -property_records=REC_FILE \
  -input_file=REC_FILE:inp -separator=property_records="\n" -subseparator=property_records=~

(oracle)$ emcli logout

Note that the property name is case-sensitive: “Lifecycle” won’t work but “LifeCycle” does. Also, the commands above are of course intended to be tinkered with. Use grep to filter out targets; search on any regular expression you can dream up.

This process is important here because we use Administration Groups to automatically propagate monitoring templates (with standardized metric thresholds for paging) to all of our OEM targets. There have been a number of times when I’ve needed to make bulk property changes and it takes a very long time to do that through the UI. These commands are much faster.

November/December Highlights

Thu, 2014-01-02 12:04

In the Oracle technical universe, it seems that the end of the calendar year is always eventful. First there’s OpenWorld: obviously significant for official announcements and insight into Oracle’s strategy. It’s also the week when many top engineers around the world meet up in San Francisco to catch up over beers – justifying hotel and flight expenses by preparing technical presentations of their most interesting and recent problems or projects. UKOUG and DOAG happen shortly after OpenWorld with a similar (but more European) impact – and December seems to mingle the domino effect of tweets and blog posts inspired by the conference social activity with holiday anticipation at work.

I avoided any conference trips this year but I still noticed the usual surge in interesting twitter and blog activity. It seems worthwhile to record a few highlights of the past two months as the year wraps up.

First, four new scripts that look very interesting:
1. Utility: getMOSpatch (doc: blog)- useful script for downloading a specific patch from MOS. I had tried something similar for RACattack back in 2011. This script written by Maris Elsins looks to be very good. I’ve downloaded this and read up on it but haven’t tried it out yet.
2. Perf: ashtop and ash_wait_chains (doc: blog 1, blog 2) – from the author of snapper, here are two more excellent tools for general performance troubleshooting and quickly pulling information from the ASH. The chains script is an especially brilliant idea – it reports from ASH using a hierarchical join on the blocking_session column. Check out Tanel’s blog posts for details and examples. I’ve used both of these scripts while troubleshooting production issues during the past month.
3. Perf/CPU: fulltime (doc: slides) – Linux specific utility to drill down into CPU-intensive processes. Similar to Tanel’s OStackProf but seems a bit more robust (runs server-side without the windows/vbscript dependencies, also brings cpu/kernel together with wait info in a single report). Rather than oradebug, this uses new lightweight linux kernel instrumentation (perf) to report a sample-based profile of what the Oracle kernel is doing by internal function. This was a collaborative effort by Craig Shallahamer and Frits Hoogland and there are several related articles on both blogs about how it works. I’ve downloaded this but haven’t tried it out yet.
4. Perf/Visualization: [Ora/Py] LatencyMap (doc: blog/sqlplus, blog/python) – very cool looking program which gives a heatmap visual representation of metrics such as I/O. I’m a huge fan of visualizations and use graphical tools daily as a DBA. Make sure to check out the recorded demo of this utility!

I love exploring utilities like these. It brings out my nerdy side a little, that’s why I mentioned them first… :) But there are a few other highlights that come to mind from the past few months too!

On the topic of utilities, I have been working with Tanel’s “tpt” script collection quite a bit during the course of my day-to-day job. I fired out a question this month to the oracle-l mailing list about other publicly posted script collections, and I got the impression that there just aren’t many script collections posted publicly! Here’s the list I came up with:

Script Collections:
- Tanel Poder (tpt), see also E2SN for even more
- Tim Hall (oracle-base)
- Kerry Osborne (2010 Hotsos Presentation), see also various blog articles for many updated scripts
- Tim Gorman
- Jeff Hunter

I’ve also read lots of other interesting stuff this month. Three things I remember off the top of my head:
- In 2012, Yury Velikanov wrote up a presentation about oracle database backups. Last month, Maris Elsins made a few tweaks and delivered the updated presentation at UKOUG. The slide deck is a worthwhile read – everybody should be able to learn something from it. If you didn’t see it when Yury first released it last year then take a few minutes to check it out.
- I was interested to read Kellyn Pot’Vin‘s slides about Database as a Service (DBaaS). This is an area I’ve been working on a lot lately and it intersects with my Operationally Scalable Practices series of articles. She’s always got good content about OEM on her blog too – being a heavy OEM user these days, I tend to read what Kellyn’s writing.
- Kyle Hailey recorded Christo Kytrovsky‘s excellent OakTable World talk about Oracle, Memory and Linux. Worth listening to sometime.

You may already be aware but I have to mention that RAC Attack has hit the accelerator lately! Through an international collaborative effort, the curriculum was updated to version 12c of the database before OpenWorld 2013 and this was followed by a rapid series of workshops. During the past three months, there have been four workshops in three different countries – and there are more coming on the calendar!

Finally, two quick “news” type mentions. First, I’ve personally tryed to avoid much of the “engineered systems” buzz (not sure why)… but I did notice the new exadata release this month. Second, oracle made an acquisition this year which was particularly significantly to me: a chicago-based company called BigMachines. You may not have heard of this company – but it happens to be mentioned on my LinkedIn profile.

These are a handful of interesting things I remember seeing over the past two months. Please leave me a comment and mention anything else that you noticed recently – I’m very interested to hear any additional highlights!