Re: new posts to an old issue

yls177 wrote:
>
> http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&threadm=3f927ab3%240%243699%24afc38c87%40news.optusnet.com.au&rnum=8&prev=/groups%3Fq%3Dyls177%2Bgroup:comp.databases.oracle.server%26hl%3Den%26lr%3D%26ie%3DUTF-8%26group%3Dcomp.databases.oracle.server%26scoring%3Dd
>
> hi, from the above... i cant post to that again. so have to link these
> two together...
>
> basically... its like this
>
> recently.. my colleagues have come up with 2 shutdown procedures and
> are as belows
>
> 1)
> alter system switch logfile
> alter system checkpoint
> shutdown abort
> startup restrict
> shutdown immediate
>
> 2)
> alter system switch logfile
> alter system checkpoint
> shutdown immediate
>
> are there any major differences between them?
>
> we noticed that (1) shutdowns much faster than (2).. this is because
> of the abort statement?

Think of it this way:

You're making a phone call. Issuing the shutdown command basically stops all new connections, so thinking only about the existing connections:

Your version 1 .... someone comes along and takes a cleaver to the phone cable (shutdown abort). Then gets out the repair tape (startup restrict) and tells everyone to hang up.

Your version 2 .... someone comes along and says 'finish your sentance and hang up now, please' and waits patiently until everyone has said their good-byes and has hung up.

If someone has walked away from their terminal (or hasn't stopped the intelligent agent), #2 could take a LONG time.

Although this seems to verge on myth - in general, it's not considered good practise to issue a shutdown abort on a regular basis. However, if you do issue a shutdown abort, it is good idea to do a startup restrict and shutdown as soon as practical thereafter. The abort leaves things in a moderately confused state that requires instance recovery, which happens automatically and generally cleanly on startup. (However, there is a small, very incredibly tiny, even miniscule, chance that the database could become bunged if a disk bump happens before the startup command.)

(Did I get that right? I think it was HJR & Quarkman that helped me understand this better <g>)
/Hans Received on Mon Dec 01 2003 - 20:55:44 CST