Friday Dec 19, 2014

Business Brief: Optimize Your Database Performance - Spend Less Time Keeping the Lights on and More Time Innovating

How are you keeping up with the challenges and demands from the business? Are you able to innovate or just keeping the lights on?

Read the latest business brief on Oracle Database Performance Management to get better insight into the challenges facing IT and find out ways to overcome them.

Read the business brief.

Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app

Thursday Dec 18, 2014

IDEXX Uses Oracle Enterprise Manager for Monitoring and Provisioning

Check out the latest SearchOracle article featuring Brett Curtis, System Administrator from IDEXX Laboratories. Read how Brett outlines how IDEXX is benefiting from using Oracle Enterprise Manager to not only monitor both middleware and database systems, but use it for provisioning as well.

Read the article.

Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app

Tuesday Nov 25, 2014

Monitoring NFS mounted file systems using EM12c

A customer recently asked me how they could monitor and alert against all the NFS mounted file systems across their datacenter. Here is a quick guide to do the same.

Read More

Monday Nov 24, 2014

Download Urls for Self Update Entities in Offline Mode

Many enterprises run their EM 12c environments in the offline mode (no direct internet connection). These customers have the additional task of downloading the plug-ins, connectors, agents, etc on a machine with access to internet, and then upload them to EM. The current solution makes the task of fetching the download url rather cumbersome, so in this blog i discuss a quick hack to list all download urls for plug-ins and agents.

Read More

Thursday Nov 13, 2014

Will the REAL Snap Clone functionality please stand up?

Possibly one of the least known pieces of functionality that is provided as part of the Enterprise Manager Cloud Control 12c product suite is the Snap Clone product. In simple terms, Snap Clone is a storage agnostic self service approach to rapidly creating space efficient clones of large databases (and by large, we're talking terabytes or more).  I blogged on that a few months back, but a few months can be an eternity in software development terms, so here's an update that covers not just the functionality in the product but also addresses some of the misleading statements some of our competitors have been making about it of recent times.

Friday Oct 24, 2014

Get Compliant with Oracle Java VM Database PSU OCT 2014 using EM12c

Check for compliance and automate patching of Oracle Database fleet using EM12c

Oracle along with its regular Quarterly Database PSU/SPU/CPU update this October 2014 released Oracle JAVA VM PSU patch, the patch is recommended to be applied to all databases in your fleet (esp. the ones that uses JAVA).  (For more information, support Note- 1929745.1 explains it in detail).
The mandate primarily is to apply the patches against the databases that use JAVAVM option. Ideally, you would need to apply it against all databases, so in case a new database is created in the ORACLE_HOME it is covered.

Oracle Enterprise Manager 12c provides support features of Compliance Management and automated Patching of databases. Using both these features you could identify the databases in your fleet that needs the patch and automate applying them.  

To get started, download the starter kit here. It contains utilities to jump start on your compliance, the kit contains a readily importable Compliance Standard and a step-by-step guide.

[Read More]

Thursday Oct 23, 2014

Oracle Enterprise Manager 12c: In-Depth Newsletter Now Available

The latest issue of the Oracle Enterprise Manager 12c newsletter is out. Read all about the latest news and information around the award winning Oracle Enterprise Manager 12c solution. This month's edition features the Oracle Application Users Group (OAUG) survey results, new study on middleware management cost reduction, and the latest details on Oracle Enterprise Manager for MySQL Database plug-in.

Read the newsletter

Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app

Monday Oct 20, 2014

Webcast: Trouble-Free Upgrade to Oracle Database 12c with Oracle Real Application Testing

Live Webcast: October 28
9:00 a.m. PST | 12:00 p.m. EST | 4:00 p.m. GMT

Oracle Database 12c contains many new capabilities including Oracle Multitenant, in-memory column stores and much more. Oracle Real Application Testing gives you verifiable functionality and performance testing capabilities to take advantage of all the new enhancements. Combining your database upgrade with Oracle Real Application Testing assures you that your database will perform as required, whether you’re implementing an in-memory column store, consolidating to a database as a service model, or doing an in-place upgrade—join us in this webcast to learn more.

Register Now

Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app

Tuesday Sep 30, 2014

Using JVM Diagnostics (JVMD) to help tune production JVMs

Contributing Author: Shiraz Kanga, Consulting Member of Technical Staff, Oracle


Tuning a production JVM involves more than merely adding more RAM to it via the -Xmx parameter. It depends upon an understanding of how your application truly behaves in a production environment. Most JVM tuning is done by developers with a simulated load in their Development or QA environment. This is unlikely to be truly representative of the production load running on production hardware with regards to proper JVM tuning.

One of the tools that actually contains real-world production data is JVM Diagnostics (JVMD). Hence it is a good idea to use data collected by JVMD for tuning your production JVMs. Note that JVMD is a component of Oracle Enterprise Manager, licensed as part of both Weblogic Management Pack and the Non-oracle Middleware Management Pack.


Figure 1. Heap Utilization and Garbage Collections for a specific JVM


In this document we are primarily addressing the Hotspot JVM. There are several aspects of tuning this JVM that we will look into:

Tuning Heap Size

The main parameters needed to tune heap size are:
  • -Xms<n>[g|m|k] is the initial and minimum size of the Java heap
  • -Xmx<n>[g|m|k] is the maximum possible size that the Java heap can grow upto

Figure 2. Heap after GC and Garbage Collection Overhead for a specific JVM


The Java Heap size here refers to the total size of the young and the old generation spaces. To start, take a look at the Heap usage chart (Figure 1) of your production JVM under maximum load in the JVMD Performance Diagnostics page. You should see some patterns in the minimum and the maximum heap sizes over time. You can use this data as a rough guide for your choice of -Xms and -Xmx with a reasonable amount of padding. After setting these you should start monitoring the garbage collection charts of your production JVMs (Figure 2) in the JVMD Live Heap Analysis page. It is useful to look into the JVMD metric called "Heap use after GC" which provides a good reflection of the actual amount of heap memory being used by your application. Ideally this metric should remain relatively steady over time with only few full garbage collections occuring. If there are too many full garbage collections then performance of your production application is impacted since GC is done by blocking threads that take a while to scan the entire heap. You can monitor this metric with the JVM GC Overhead% chart on the same page of JVMD. Garbage collection overhead is the percentage of total time spent in garbage collection. Increasing -Xmx can help to make these happen less frequently but actually it is time to dig deeper into your tuning options.

The key questions that you need to answer are - How frequently does garbage collection take place, How long does each collection take and what is the actual memory used (i.e. heap after GC). Also be sure that you NEVER make the heap size larger than the available free RAM on your system as disk will decrease performance as RAM will start getting swapped to disk.

The Sun HotSpot JVM relies on generational garbage collection to achieve optimum performance. The -XX:SurvivorRatio command line parameter could further help in tuning garbage collection.

The Java heap has a young generation for newly created objects and an old generation for long lived objects. The young generation is further subdivided into the Eden space where new objects are allocated and the Survivor space where new objects that are still in use can survive their first few garbage collections before being promoted to old generations. The Survivor Ratio is the ratio of Eden to Survivor space in the young object area of the heap. Increasing this setting optimizes the JVM for applications with high object creation and low object preservation. In applications that generate more medium and long lived objects, this setting should be lowered from the default and vice versa.

For example, -XX:SurvivorRatio=10 sets the ratio between each survivor space and eden space to be 1:10. If survivor spaces are too small, they will overflow directly into the old generation. If survivor spaces are too large, they will be empty. At each GC, the JVM determines the number of times an object can be copied before it is tenured, called the tenure threshold. This threshold should be set to keep the survivor space half full.

Most tuning operations represent a trade-off of some type or another. In the case of garbage collection the trade-off usually involves the memory used v/s throughput and latency.
  • The throughput of a JVM is measured in terms of the time spent doing garbage collection vs. the time spent outside of garbage collection (referred to as application time). It is the inverse of GC overhead mentioned above and represents the amount of work done by an application as a ratio of time spent in GC. Throughput can be tuned with -XX:GCTimeRatio=99 where 99 is the default which represents a 1% GC overhead.
  • Latency is the amount of time delay that is caused by garbage collection. Latency for GC pauses can be tuned by specifying rhe maximum pause time goal with the command line option -XX:MaxGCPauseMillis=<N>. This is interpreted as a hint that pause times of <N> milliseconds or less are desired. By default, there is no maximum pause time goal. If a pause time goal is specified, the heap size and other garbage collection related parameters are adjusted in an attempt to keep garbage collection pauses shorter than the specified value. Note that these adjustments may cause the garbage collector to reduce the overall throughput of the application and in some cases the desired pause time goal cannot be met.
Some lesser-known options are about permanent generation space which is used by the JVM itself to hold metadata, classes structures and so on:
  • -XX:PermSize=<n>[g|m|k] is the initial and minimum size of the permanent generation space.
  • -XX:MaxPermSize=<n>[g|m|k] is the maximum size of the permanent generation space. If you ever get the message java.lang.OutOfMemoryError: PermGen space then it means that your application is loading a very large number of classes and this should be raised.
  • -Xss=<n>[g|m|k]is the size of the thread stack. Each thread in a Java application has its own stack. The stack is used to hold return addresses, arguments to functions and method calls, and so on. The default stack size setting for a thread in Java is 1MB. In a highly multi-threaded system, like an application server at any given point in time there are multiple thread pools and threads that are in use so this may need to be reduced. Since stack size has to be allocated in contiguous blocks and if the machine is being used actively and there are many threads running in the system you may encounter an OutOfMemory error even when you have sufficient heap space. Recursive code can quickly exhaust the stack and if you use such code then you may need to increase the -Xss setting. However, if you see java.lang.OutOfMemoryError: unable to create new native thread then you may have too many threads, or each thread has a large stack; so you may need to decrease it.

Tuning Garbage Collection Algorithm

Garbage collection is expensive. Generational garbage collectors have the JVM  memory divided into several spaces.
  • Eden space: All objects are placed here when first created
  • Survivor spaces: One or more regions where objects mature
  • Tenured space: Where long lived objects are stored
  • Permanent generation: This area is only used by the JVM itself to hold metadata, such as data structures for classes, methods, interned strings
One thing that people often forget to try, is to lower the amount of garbage being created in the first place. There are a lot of ways to do this which are specific to the application/code that is being written. This often involves techniques such as using StringBuilder/StringBuffer instead of Strings, lowering the amount of logging, etc.

There are several GC algorithms which are available to be used in a Java VM. The following command line options allow to use a specific GC algorithm:
  • -XX:+UseSerialGC uses a single threaded, young generation, and old generation garbage collector (Normally this is a poor choice and should be used only for small Java heap sizes such as -Xmx256m or smaller)
  • -XX:+UseParallelGC utilizes a multithreaded (parallel) garbage collector for the young generation and a single-threaded garbage collector for the old generation space in parallel.
  • -XX:+UseParallelOldGC uses a multithread garbage collector for both the young and old generations.
  • -XX:+UseParNewGC -> enables a multithreaded, young generation garbage collector
  • -XX:+UseConcMarkSweepGC -> enables the VM’s mostly concurrent garbage collector. It also auto-enables -XX:+UseParNewGC (use if If you are not able to meet your application’s worst case latency requirements due to full garbage collection duration being too long)
  • -XX:+UseG1GC -> garbage first collector (default in java 7, can be also used in latest releases of Java 6)
In practice, the default in Java 6 is ParallelGC and in Java 7 it is the G1GC. Changing the algorithm requires detailed analysis of the application behavior. If you see a nice regular sawtooth chart in the heap usage you may not need any changes at all. If not, we recommend trying out each GC algorithm under a realistic load and then comparing it to the default algorithm's behavior under the same load. Usually you will find that the default algorithm outperforms the new setting and that there is no reason to change it.

As you can see, tuning the JVM and it's garbage collectors is largely a trade-off between space and time. If you had infinite heap space then you would never need to collect garbage. Inversely, if you could tolerate infinite time delays, then you could run a cleanup as frequently as you like and keep the heap compact. Clearly, both those situations are impossible. Finding the right middle ground that is right for you requires careful balancing act based on understanding how GC works and what the application requires.

References:

Java SE 6 HotSpot Virtual Machine Garbage Collection Tuning http://www.oracle.com/technetwork/java/javase/gc-tuning-6-140523.html

Summary of Enterprise Manager general session at Oracle OpenWorld 2014

Oracle OpenWorld is at full speed now and this morning we just delivered our Enterprise Manager general session. We realize that probably the majority of the thousands of readers of our blog are not attending OpenWorld so that's why we have created a summary of the Tweets that were sent during the session
(in case you are not familiar with Twitter timelines, please read from the bottom to the top for a chronological order of the presentation) 

For those that want to see the full presentation, we've uploaded them to our SlideShare account for your convenience .

For all Enterprise Manager related sessions at Oracle OpenWorld 2014, please take look here and let us know which one you'd like to see summarized or even see the full deck?

Sunday Sep 28, 2014

Oracle Announces Oracle Enterprise Manager for MySQL Database

To help customers simplify management of complex IT environments, Oracle is extending Oracle Enterprise Manager capabilities to MySQL databases. With this new offering, customers can manage deployments of MySQL, either on-premises or in a cloud. Existing users of Oracle Enterprise Manager can now easily add MySQL to their environments. With this capability, customers can manage their applications and technology stack, including web and departmental applications that rely on MySQL, all from a single console.

With Oracle Enterprise Manager for MySQL Database, customers can benefit from:

  • Auto-discovery of MySQL targets
  • Availability monitoring
  • Configuration and metrics collection
  • Performance dashboards
  • Configurable thresholds

Watch the Demo:

MySQL Enterprise Edition customers can download Oracle Enterprise Manager for MySQL Database, Release 5.5 and higher, which is available on Oracle Linux and other Linux distributions, Microsoft Windows, and Oracle Solaris. Watch the demo for more details.


Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app

Wednesday Sep 17, 2014

Stay Connected at Oracle OpenWorld

Follow Oracle Enterprise Manager 12c @ Oracle OpenWorld

If you are planning to attend OpenWorld this year, make sure you maximize the full conference experience—stay connected to all the Oracle Enterprise Manager 12c activities.

For the complete list of OpenWorld events and activities, read the Oracle Enterprise Manager 12c Focus on Doc.

Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app

Tuesday Sep 16, 2014

Oracle OpenWorld: Oracle Enterprise Manager 12c General Session

Heading to Oracle OpenWorld?

Be sure to check out the Oracle Enterprise Manager 12c general session, Drive the Future of Self-Service IT with Oracle Enterprise Manager 12c [GEN8250].

Session Abstract:

Successful strategies for cloud computing and self-service IT demand a unified management solution that provides visibility, insight, and control across the IT landscape. In this session, key representatives from Oracle Enterprise Manager Product Development will discuss customer and partner experiences in deploying and managing large-footprint private cloud environments encompassing Oracle Applications, Oracle Fusion Middleware, Oracle Database, and Oracle Engineered Systems. In the second part of the session, attendees will get a sneak preview of several exciting new offerings in the Oracle Enterprise Manager family. Don’t miss this opportunity to glimpse the future of Oracle’s systems management offerings.

For the complete list of OpenWorld sessions, demos and hands-on labs, read the Oracle Enterprise Manager 12c Focus on Doc for more.


Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app

Monday Sep 15, 2014

The Countdown is on—12 Days to Go!

Oracle Enterprise Manager 12c @ Oracle OpenWorld 2014

Oracle Enterprise Manager 12c, in its fourth year, has seen record levels of customer adoption. We are excited to showcase many of these customers throughout our OpenWorld activities, sessions, hands-on labs and DEMOgrounds this year.

With Oracle Enterprise Manager's large presence at OpenWorld, we've provided a variety of resources that you can use to follow all the Oracle Enterprise Manager activities and events.

Highlights:

  • Unprecedented number of customer sessions with over 50 presenting or co-presenting this year.
  • Full-day track on Oracle Enterprise Manager 12c at the Sunday User Group Forum sponsored by the IOUG.
  • General Session and over 40 Oracle-authored track-sessions on Oracle Enterprise Manager.
  • 19 Dedicated Oracle Enterprise Manager demopods in the Oracle DEMOgrounds.
  • 13 Oracle Enterprise Manager 12c hands-on labs providing deep-dive experience led by Oracle experts.

For the complete list of sessions, demos and hands-on labs, read the Oracle Enterprise Manager 12c Focus on Doc for more.



Stay Connected:
Twitter |
Facebook | YouTube | Linkedin | Newsletter
Download the Oracle Enterprise Manager 12c Mobile app
About

Latest information and perspectives on Oracle Enterprise Manager.

Related Blogs




Search

Archives
« July 2015
SunMonTueWedThuFriSat
   
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
 
       
Today