topic Re: Does SG SMS for HP-UX 11.31 support previos qio-named files?? in Operating System - HP-UX

Does SG SMS for HP-UX 11.31 support previos qio-named files??

Ruslan Amalatov — Thu, 27 Nov 2008 15:04:09 GMT

Hello all,

Does anybody know whether the ServiceGuard Storage Management Suite (formly known as ODM 5.x) support the well-known previous qio-naming schema for Oracle datafiles or not?

Ex:
# ll /test2/orcl10g/
total 56623152
-rw-rw---- 1 oracle dba 23622328320 Nov 27 16:18 .test01.dbf
-rw-rw---- 1 oracle dba 1073750016 Nov 27 16:28 .test02.dbf
-rw-rw---- 1 oracle dba 4294975488 Nov 27 16:25 .undotbs2.dbf
lrwxr-xr-x 1 root sys 23 Nov 27 16:27 test01.dbf -> .test01.dbf::cdev:vxfs:
lrwxr-xr-x 1 root sys 23 Nov 27 16:28 test02.dbf -> .test02.dbf::cdev:vxfs:
lrwxr-xr-x 1 root sys 25 Nov 27 16:27 undotbs2.dbf -> .undotbs2.dbf::cdev:vxfs:
#

I've got the following error when tried to start up my Oracle DB with QuickIO enabled in init.ora (disk_asynch_io = true)

SQL> startup;
ORACLE instance started.

Total System Global Area 117440512 bytes
Fixed Size 2054288 bytes
Variable Size 92276592 bytes
Database Buffers 16777216 bytes
Redo Buffers 6332416 bytes
Database mounted.
ORA-01110: data file 5: '/test/orcl10g/test01.dbf'
ORA-01115: IO error reading block from file 5 (block # 1)
ORA-27070: async read/write failed
HPUX-ia64 Error: 15: Block device required

SQL>

When I turn the disk_asynch_io parameter off the DB starts as normally as ussual but of course in a synchronous mode.

Ruslan Amalatov

Re: Does SG SMS for HP-UX 11.31 support previos qio-named files??

Duncan Edmonstone — Thu, 27 Nov 2008 16:51:27 GMT

I'm not entirely sure, but I do know that ODM is supposed to perform better that QIO anyway, so you should look to convert the files back to normal file (I seem to recall a command called qio_convertdbfiles which can be use to convert QIO files back to normal files), and then ensure the ODM library is linked into Oracle.

HTH

Duncan

Re: Does SG SMS for HP-UX 11.31 support previos qio-named files??

Ruslan Amalatov — Fri, 28 Nov 2008 15:31:55 GMT

Hi Duncan,

Thank you for your reply. I agree with you about new better enchancements in the new ODM version. But as long as I know it does not provide any way to enable caching on filesystem level and this is an absolute requirement in my case. That's why the only choice for my customer is to use the cached qio.

Any idea for the issue?

Ruslan Amalatov

Re: Does SG SMS for HP-UX 11.31 support previos qio-named files??

Ruslan Amalatov — Tue, 09 Dec 2008 11:44:43 GMT

Hi folks,

Hereunder is what I got from Oracle Support guys:

01-DEC-08 19:35:06 GMT

Its actually the same.

Oracle (for HP only) always uses async I/O regardless of the value of init settings
(disk_asynch_io = FALSE and filesystemio_options = none).
The parameter filesystemio_options = none doesn't work.

Oracle always opens /dev/async successfully only if the /dev/async HP-UX
device driver is properly configured for read and write. This is irrespective
of whether the DISK_ASYNC_IO parm is set to TRUE.

03-DEC-08 10:35:04 GMT

New info : amalatov@i-teco.ru
Hello,

The information you have provided seems to me a little bit confusing. Could you please give me a link to a documentation or an official note about that non-standard Oracle Database
behavior on HP-UX.
If you cannot do this, am I right considering these 2 parameters to be safely ignored and to be sure that all datafile I/O is asynchronous when the /dev/async driver is properly configured?

Ruslan Amalatov
I-Teco

05-DEC-08 20:15:19 GMT

Thats actually from an internal bug from the HP porting team but let me find something official for you.

05-DEC-08 20:17:23 GMT

Here is a note on this, slightly different problem, but same thing:

Article-ID: Note 302801.1
Circulation: PUBLISHED (EXTERNAL)
Folder: ST.Server.DBA.Admin
Topic: Managing Databases
Title: How to disable asynch_io on HP to avoid Ioctl Async_config
Error Errno = 1

Best regards,
Ruslan Amalatov
I-Teco