Comments on: Private Redo

By: Dird

Dird — Tue, 23 Oct 2012 09:27:33 +0000

Oh, it’s private redo buffers -_

By: Dird

Dird — Tue, 23 Oct 2012 09:00:21 +0000

Hi,

How would you check which ones are private or public? I can’t guess a column based on the names in that table :x
Would x$kcrfstrand show information from all instances on a RAC or only the one it is run on?

Interesting stuff :o I thought only 1 buffer per instance until I started reading your book (now on page 15 >_<)

Mike

By: Tanel Poder

Tanel Poder — Fri, 28 Sep 2012 01:49:35 +0000

I’ve seen BABEFACE somewhere too :-)

By: Yong Huang

Yong Huang — Tue, 25 Sep 2012 20:29:30 +0000

I’ve seen DEADBEEF on Solaris. According to http://en.wikipedia.org/wiki/Hexspeak it has a history and is conventionally used to “mark newly allocated areas of memory that had not yet been initialized”.
I think we can also say the private threads that have been used are those with non-zero pvt_strand_state_kcrfa_cln.

By: Lasse Jenssen

Lasse Jenssen — Mon, 24 Sep 2012 18:19:30 +0000

I must say I admire your curiosity. It’s always interesting to read your articles, even if it’s just for a laugh.

By: Jonathan Lewis

Jonathan Lewis — Tue, 18 Sep 2012 11:43:10 +0000

Sagizvi,

No, not the last time I looked.

It’s worth noting that the default size of the flashback log buffer is (was) twice the size of the redo log buffer – so if you see waits for the flashback log buffer then the remedy is to increase the size of the redo log buffer.

By: sagizvi

sagizvi — Tue, 18 Sep 2012 06:42:42 +0000

Hi Jonathan.
What about flashback log buffer ? does oracle use private log buffers as well ?

By: Mladen Gogala

Mladen Gogala — Tue, 18 Sep 2012 01:15:49 +0000

I couldn’t believe it! I checked and it’s true:

$ perl -e ‘printf(“%X\n”,3735928559);’
DEADBEEF

mgogala@CVPS007153 ~

Jonathan, you’ve just made my day, not in the dirty Harry sense.