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May 2013

MobaXterm 6.3…

Thanks to Norman Dunbar for pointing out that MobaXterm 6.3 has been released. You can find the download and changelog in the usual place.

I’ll be interested to see how the performance improvements to SFTP work out. I’ve seen some issues with this during transfers of large files before. The built in NFS and VNC servers sound interesting too. I can think of one situation where the NFS server would come in really handy. :)

Great stuff!

Cheers

Tim…

UltraEdit 4.0 for Mac/Linux…

UltraEdit 4.0 has been released for Mac and Linux. The downloads are in the usual place. You can see the latest changelogs here (Mac, Linux).

Fun, fun, fun…

Cheers

Tim…

Clustering_factor

Cost Based Oracle – Fundamentals (November 2005)

But the most interesting function for our purposes is sys_op_countchg(). Judging from its name, this function is probably counting changes, and the first input parameter is the block ID portion (object_id, relative file number, and block number) of the table’s rowid, so the function is clearly matching our notional description of how the clustering_factor is calculated. But what is that 1 we see as the second parameter?

New Version Of XPLAN_ASH Tool - Video Tutorial

A new major release (version 3.0) of my XPLAN_ASH tool is available for download.

You can download the latest version here.

In addition to many changes to the way the information is presented and many other smaller changes to functionality there is one major new feature: XPLAN_ASH now also supports S-ASH, the free ASH implementation.

If you run XPLAN_ASH in a S-ASH repository owner schema, it will automatically detect that and adjust accordingly.

XPLAN_ASH was tested against the latest stable version of S-ASH (2.3). There are some minor changes required to that S-ASH release in order to function properly with XPLAN_ASH. Most of them will be included in the next S-ASH release as they really are only minor and don't influence the general S-ASH functionality at all.

Important !! Clustering Factor Calculation Improvement (Fix You)

Believe me, this article is worth reading I’m currently not allowed to discuss Oracle 12c Database goodies but I am allowed to discuss things perhaps initially intended for 12c that are currently available and already back-ported to 11g. This includes a wonderful improvement in the manageability of how the Clustering Factor (CF) of an index can now […]

The year of the “back-fill” author…

I recently filled in this years ACE Director self assessment survey. Among other things, as part of that process I check how many articles, blog posts and forum answers I’ve posted over the year.

Whilst getting these numbers I noticed about 50% of articles I put live this year weren’t promoted to the front page as new articles because they were “back-fill”, written on general topics that haven’t really changed over the years. Of the last 6 articles I’ve written, only 1 has made it to the front page as a “new” article. Some of these back-fill articles were prompted by answering readers questions and some by situations that have come up at work. They all go live on the website, but I’d feel silly posting them as a new article. :)

Using Optimizer Hints for Oracle Performance Tuning

My next Embarcadero sponsored webinar will be on May 14 and is entitled Using Optimizer Hints for Oracle Performance Tuning.

Register now!

SLOB

Anyone who has used Kevin Closson’s “Silly Little Oracle Benchmark” will want to know about his significantly updated SLOB2.

Webinars

Reminder

The “Smarter Stats in 11g” webinar is on tomorrow (Monday 10th):

Update:

I’ve scheduled a third time for the repeats of the free webinar  ”Smarter Statistics in 11g” on June 10th – 1:00 pm BST.  The 6:00 pm is already full, but there are still places on the 9:00 pm showing.  As before we’re using GoToWebinar as the supply mechanism, and we’ve limited access to 100 people (so if you do register and can’t attend, please remove yourself from the list). The recordings of the webinar will be available to registered listeners for 7 days after the event.

Links to register for the  event:

When does an Oracle process know it’s on Exadata?

When an Oracle process starts executing a query and needs to do a full segment scan, it needs to make a decision if it’s going to use ‘blockmode’, which is the normal way of working on non-Exadata Oracle databases, where blocks are read from disk and processed by the Oracle foreground process, either “cached” (read from disk and put in the database buffercache) or “direct” (read from disk and put in the process’ PGA), or ‘offloaded mode’, where part of the execution is done by the cell server.

The code layer where the Oracle database process initiates the offloading is ‘kcfis’; an educated guess is Kernel Cache File Intelligent Storage. Does a “normal” alias non-Exadata database ever use the ‘kcfis’ layer? My first guess would be ‘no’, but we all know guessing takes you nowhere (right?). Let’s see if a “normal” database uses the ‘kcfis’ functions on a Linux x64 (OL 6.3) system with Oracle 11.2.0.3 64 bit using ASM.