topic Re: archiver in Operating System - HP-UX

archiver

jok llamera — Wed, 13 Mar 2002 08:49:10 GMT

hi fellas,

Im sure one of you here is an Oracle DBA, Im using HPUX 11.0 and I have a question when writing a data from redolog(RAW) to the archivelog files(Filesystem). Does it bypasses the oracle buffer cache or not?

Thanks,
joks

Re: archiver

Carlos Fernandez Riera — Wed, 13 Mar 2002 10:38:45 GMT

And the answer is NO.

You can check it with tusc:

tusc -f -o /tmp/tusc.log -a -s open,read,write -p PID

PID is PID of ora_arch_$ORACLE_SID

It seem to open redolog file for read only, open a new redolog_on_disk file and write while read.

Regards.

Re: archiver

Andreas D. Skjervold — Wed, 13 Mar 2002 13:50:47 GMT

Hi

The archiver will use the Redo Log Buffer.

The archiver will:
1) read the control file to find any unarchived logs,
2) open online redo log members to be read,
3) allocate redo log buffers,
4) read the online redo log,
5) fill redo log buffers,
6) write to the archive files,
7) update control file with new information,
8) starts the loop again.

Andreas

Re: archiver

Ryan Kogelheide — Thu, 14 Mar 2002 09:13:53 GMT

Andreas,

That's interesting. I've obviously misunderstood something about how the archiver works.

What I always imagined is that it would read and edit the control file while doing a simple OS copy.

Why does it need to work with redo buffers?

Ryan