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Solaris

Remote syslog from Linux and Solaris

Auditing operations with Oracle Database is very easy. The default configuration, where SYSDBA operations go to ‘audit_file_dest’ (the ‘adump’ directory) and other operations go to the database may be sufficient to log what is done but is definitely not a correct security audit method as both destinations can have their audit trail deleted by the DBA. If you want to secure your environment by auditing the most privileged accounts, you need to send the audit trail to another server.

Oracle Solaris 11.4 Public Beta Released

Yesterday the Oracle Solaris 11.4 Beta was released to the public. You can download it from OTN to have your go with it. Please read the documentation to learn all about the new and improved features. And remember that you can always contact me in case you need training on the most advanced Operating System […]

Back to the future

Back in 1993 I started my career at Oracle as a Unix System Administrator with a specialization in Sun Solaris. I have been using the Solaris operating system ever since the Solaris 2.0 Early Adopter program started in 1991. Those were the days ;-) In late 1998 I switched from being a system administrator to […]

Dtrace probes in Oracle 12c… v$kernel_io_outlier is populated by dtrace!!

Oracle 12c certainly has some great features, but for the performance guy like myself, performance monitoring features are particularly interesting.  There are three new v$ tables that track anomalies in the IO path.  The idea is to provide more information about really poorly performing IO that lasts more than 500ms.

  • V$IO_OUTLIER : tracks the attributies of an IO.  The size, latency as well as ASM information is recorded.
  • V$LGWRIO_OUTLIER : tracks information specifically on Log writer IO.

These two tables are going to be useful to monitor when performance issues occur.  I can already see the SQL scripts to monitor this activity starting to pile up.  But, there is one little extra table that dives even further into the IO stack using Dtrace.

Dtrace probes in Oracle 12c… v$kernel_io_outlier is populated by dtrace!!

Oracle 12c certainly has some great features, but for the performance guy like myself, performance monitoring features are particularly interesting.  There are three new v$ tables that track anomalies in the IO path.  The idea is to provide more information about really poorly performing IO that lasts more than 500ms.

  • V$IO_OUTLIER : tracks the attributies of an IO.  The size, latency as well as ASM information is recorded.
  • V$LGWRIO_OUTLIER : tracks information specifically on Log writer IO.

These two tables are going to be useful to monitor when performance issues occur.  I can already see the SQL scripts to monitor this activity starting to pile up.  But, there is one little extra table that dives even further into the IO stack using Dtrace.

Analyzing IO at the Exadata Cell level… a simple tool for IOPS.

Lately I have been drawn into to a fare number of discussions about IO characteristics while helping customers run benchmarks.  I have been working with a mix of developers, DBAs, sysadmin, and storage admins.  As I have learned, every group has there own perspective – certainly when it comes to IO and performance.

  • Most DBA’s want to see data from the DB point of view so AWR’s or EM works just fine.
  • Most System Admin’s look at storage from the Filesystem or ASM disk level.
  • Storage Admins want to see what is going on within the array.
  • Performance geeks like myself, like to see all up and down the stack <br />
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Analyzing IO at the Exadata Cell level… a simple tool for IOPS.

Lately I have been drawn into to a fare number of discussions about IO characteristics while helping customers run benchmarks.  I have been working with a mix of developers, DBAs, sysadmin, and storage admins.  As I have learned, every group has there own perspective - certainly when it comes to IO and performance.

  • Most DBA's want to see data from the DB point of view so AWR's or EM works just fine.
  • Most System Admin's look at storage from the Filesystem or ASM disk level.
  • Storage Admins want to see what is going on within the array.
  • Performance geeks like myself, like to see all up and down the stack <br />
</li></ul></div>

    	  	<div class=

Solaris Eye for the Linux Guy… Part III (hugepages = ISM)

This post has been a long time coming but recently, I have started working on some SPARC SuperCluster POC’s with customers and I am getting re-acquainted with my old friend Solaris and SPARC.

If you are a Linux performance guy you have likely heard of HugePages.   Huge pages are used to increase the performance of large memory machines but requiring fewer TLB‘s .  I am not going to go into the details TLB’s, but every modern chip supports multiple memory page sizes.

So how do you get huge pages with Solaris?

Do nothing – it is the DEFAULT with Oracle running on Solaris.

Tuning is in the eye of the beholder… Memory is memory right?

It is human nature to draw from experiences to make sense of our surroundings.  This holds true in life and performance tuning.   A veteran systems administrator will typically tune a system different from an Oracle DBA.  This is fine, but often what is obvious to one, is not to the other.  It is sometimes necessary to take a step back to tune from another perspective.

I recently have ran across a few cases where a customer was tuning “Sorts” in the database by adding memory. Regardless of your prospective, every one knows memory is faster than disk; and the goal of any good tuner is to use as much in memory as possible.   So, when it was noticed by the systems administrator that the “TEMP” disks for Oracle were doing a tremendous amount of IO,  the answer was obvious right?

VirtualBox and Solaris 10 Guest Additions

Just a quick post really to save you some time-as it stands the guest additions for Solaris 10 are broken with Virtual Box 4.1.0. When I tried to install them in my Solaris 10 U9 guest, everything worked until the vboxsf module should have been loaded. The output from dmsg is as follows:

Aug 30 18:45:33 unknown genunix: [ID 819705 kern.notice] /usr/kernel/fs/amd64/vboxfs: undefined symbol
Aug 30 18:45:33 unknown genunix: [ID 819705 kern.notice] /usr/kernel/fs/amd64/vboxfs: undefined symbol
Aug 30 18:45:33 unknown genunix: [ID 819705 kern.notice] /usr/kernel/fs/amd64/vboxfs: undefined symbol
Aug 30 18:45:33 unknown genunix: [ID 472681 kern.notice] WARNING: mod_load: cannot load module 'vboxfs'

I’m running Virtual Box 4.1 on Windows 7. When I tried to check for updates the application returned “you are already running the current version”. However, checking the Downloads section of the website I found 4.1.2-which I’m trying now.

The workaround for 4.1.0 is to install older guest additions, see http://forums.virtualbox.org/viewtopic.php?f=20&t=43212 for more detail.