2010-04-16

are my resources in favored place?

On a 11gR1 Oracle Cluster I had an issue with some resources not in their favored place.
While investigating, I had to get the affected resources fast (at least faster than reading a huge list of resources manually and think if they match the rules).

This brought me to a small script:

crs_stat -f | awk ' BEGIN { FS="="
c=0}
/^NAME=/{n=$2}
/TYPE=/{t=$2}
/HOSTING_MEMBERS=/{hm=$2}
/PLACEMENT=/{p=$2}
/TARGET=/{g=$2}
/STATE=/{s=$2;
ch=s
gsub("ONLINE on ", "",ch)
if( (p=="favored") && !( index(hm,ch)>0 ) ) {
printf("%-30s%-20s%-17s%-15s%-30s\n", n, " should be located on ", hm, " but has STATE: ", s) ;
c+=1 ;
}
}
END { exit c }'


It prints out a line for every resource which has a favored placement, but currently is not on any HOSTING_MEMBERS.

I'm sure it's not the best awk-code, but it's fine for me.

To use it in other scripts (e.g. monitoring) I can use | wc -l to get the number of suboptimal located resources or just get the return value $?

2010-03-22

developers joke

Yesterday evening I had to deal with the product of a really funny Oracle developer:
I had requested a CRS patch for Bug:8328904 under really high preassure (Management involved). With a target date of 3rd week of March 2010, I got the patch on 19-Mar-2010 about 2pm local time. Just in time!
So I had the fun to patch a test system on Sunday evening. As allways, it's not that easy as it sounds:
after a slow, but successful preparation of one node and a really easy patch, at restart of the CRS I got
/etc/init.d/init.crs: [[: not found

Ok. I knew this Patch was knitted with really hot needles, so after some checking we applied this diff:
 72c72
< if [[ "$CMD" = "init.crs" && "$PARENT_CMD" != "startpar" ]]; then
---
> if [ "$CMD" = "init.crs" ] && [ "$PARENT_CMD" != "startpar" ]; then


All the patching ended at Monday, 2am.

Of course, I updated my SR on Monday morning with this slightly detail.
The answer was overwhelming:

/etc/init.d/init.crs: [[: not found encountered while startup is a known issue and bug is already filed.( bug# 9131555).

The problem is with the 11.1.0.7. bundle 2 . Since the patch was created on top of 11.1.0.7 bundle 2 hence the same error got passed on. The workaround is correct and is same as mentioned in the above mentioned bug. So no problem it is a supported workaround.

What a funny developer!
delivering a patch for a escalated but just in time, delivering another known within it.

Who can tell me why i was not laughing?

2010-03-17

Job, hobby or passion?

In my last post I summarized the answers I got on a mailing list for the short question:
what ist the fastest SQL you can create?
maybe the most remarkable answer was
I think y'all need a hobby- and one that doesn't include oracle!


Well, maybe I have to answer. Which is not that easy.
Let's try to confine a little bit: Let's start with Job. I see a job as a work which I get paid for. So i need a job to make a living.
At first view a hobby is a totally contradiction to a Job: I do it at my own will and possible even spend money to do it. A hobby is something I do to have fun.
But sometimes it's not that easy.
Even if job and hobby are a contradiction in money and choice, they are not imperatively a contradiction in fun.
Assume, you have a job which at the same time is fun. Why not enjoy this: instead of paying for fun, you get paid for! Maybe it's ok if I call it an avocation?
Of course, it's not that easy all the time, but nothing is that easy, not even a hobby ;-)
I see one more bonus in this situation: I assume I'm quite good in the tasks I get paid for. And at least at the moment I get a fair salary. I hope, both will at least stay at this level for a long time.

This all leads me to an answer:
I have a job in IT, especially Oracle. Why do I need a hobby?

2010-03-16

fastest SQL?

Recently I asked what ist the fastest SQL you can create? on oracle-l mailing list.
It was a kind of challenge. But not a real clever one.
I was more interrested in the way people think and react to this question than in a particular SQL or result.

Here are some summaries for those who are interrested:
There where 33 replies (until now), these can be grouped by some categories (some mails belong to more than one):

select 1 from dual; was suggested by Niall Litchfield and Kevin Lidh.
Don Granaman showed an imprived version with a view on sys.v_dual, but Niall and Norman Dunbar argued, that's what fast_dual was introduced for.

Niall and Wolfgang Breitling asked for better specifications for the quest, which I left open by intention.

Another approach started with exit; by Daniel Fink. Robert Freeman called this not a SQL, but Grant Allen (--) and Jaromir D.B. Nemec ("empty statement") tried the same direction.
Job Miller suggested the qhole quest as a kind of trick question With the answer You look at the statement/business logic and decide that you don't need to run that statement at all. and Daniel gave a real world example for this effect.


Toon Koppelaars and Andre van Winssen both suggested query result cache. I tried to test this but could not find a suficient measurement. Brandon Allen raised the method by checking elapsed_time down to microseconds from v$sql/v$sqlstats.

Wolfgang did one step further with his client side cache.

A discussion about other products like purple and Mauve by Jack C. Applewhite, Christopher Boyle, John Piwowar and Jason Heinrich.

I think y'all need a hobby- and one that doesn't include oracle! by Kellyn Pedersen and Kathy Duret seems to be worth a seperate blog!

2010-03-12

NOTE:Unident of disk

I just wondered where the lines

*** 2010-03-12 10:25:13.862
NOTE:Unident of disk:/appl/oracle/asm_disks/c3t60014380024D39280000A000039B0000d0s0_eva
NOTE:Unident of disk:/appl/oracle/asm_disks/c3t60014380024D39280000A00003A10000d0s0_eva

came from in my +ASMS744_rbal_3119.trc trace file every minute.

As i did not find any matches for NOTE:Unident of disk in MOS, I tried to open a SR there. Just in the preperation, I checked the status of this particular Disk:

select header_status, path
from v$asm_disk
where path like '%c3t60014380024D39280000A000039B0000d0s0%';

HEADER_STATUS PATH
------------- ------------------------------------------------------------------
CANDIDATE /appl/oracle/asm_disks/c3t60014380024D39280000A000039B0000d0s0_eva


So I added these disks to a DiskGroup and the trace file did not grow any further.

I didn't found anything about Unident of disk in the docu, MOS or google. sadly.

2009-12-31

USL in excel - without the need to read

Neil Gunther created a nice small excel spreadsheet to calculate the key values sigma and kappa for his Universal Scalability Law - primarily for the use in his GCaP class. Beside some other problems with excels numerical precision and Negative Scalability Coefficients in Excel I dislike the ugly 'create a graphic, let it show a trendline and it's coefficients, add these into some cells and continue' step. Fortunately, Scott Roberts has created some google spreadsheets where he implemented a real formula (as google spreadsheets does not support trendlines and their coefficients). These are mentioned in Neils blog entry Scalability in a Spreadsheet - google style.
As this method is also available in excel, I decided to extend Neils excel by some functions to avoud the read and insert part.
sscalc-class_berx1 It is not just easier to apply, it's also more accurate as the coefficients shown in the graph are shown with small rounding.

With the formula shown here:
sscalc-class_berx2

Don't be confused by the semicolons in the formula, depending on your language settings, excel sometimes use colon or semicolon to separate fields of the formula.
Here the detailed fields I've added:

Field H11:
Field I8:=INDEX(LINEST($G8:$G14;$F8:$F14^{1,2}; FALSE); 1)
Field I9: =INDEX(INDEX(LINEST($G8:$G14;$F8:$F14^{1,2}; FALSE;TRUE); 1);2)
Field I10: =INDEX(INDEX(LINEST($G8:$G14;$F8:$F14^{1,2}; FALSE;TRUE); 1);3)
Field I11: =INDEX(INDEX(LINEST($G8:$G14;$F8:$F14^{1,2}; FALSE;TRUE); 3);1)

I hope i used the LINEST function correct, and this might help others to reduce one step while playing with USL.

2009-12-30

MOS can't count

MOS (the flash version) can not even count up to 3:

Can someone show me the hidden element?