Simpler Navigation for Servers and Operating Systems - Please Update Your Bookmarks
Completed: a much simpler Servers and Operating Systems section of the Community. We combined many of the older boards, so you won't have to click through so many levels to get at the information you need. Check the consolidated boards here as many sub-forums are now single boards.
If you have bookmarked forums or discussion boards in Servers and Operating Systems, we suggest you check and update them as needed.
Showing results for 
Search instead for 
Did you mean: 

Single Writer Lock and hp-ux

Single Writer Lock and hp-ux

Hi All,
I found a White paper about Single Writer Lock on Solaris.

Does the issue affect hp-ux or not ?
Online-JFS(Direct I/O) or Veritas Quick I/O avoid the issue ?

I think the whitepaper explains general issue of Unix Filesystems(UFS,VxFS).

Best Regards,

Dietmar Konermann
Honored Contributor

Re: Single Writer Lock and hp-ux

I think, you would need the Veritas Quick I/O option to get around this issue. As far as I know, also VxFS with Direct I/O may be affected by single writer lock contention.

Best regards...
"Logic is the beginning of wisdom; not the end." -- Spock (Star Trek VI: The Undiscovered Country)

Re: Single Writer Lock and hp-ux

moving to raw device you will solve this problem.

Re: Single Writer Lock and hp-ux

Thanks for All,
I want to get a evidence that single writer lock affect to Oracle performance.
I have hp glance,this tool helps me for the purpose ?

I know raw volume is best for performance,but it's difficult to change now.


Re: Single Writer Lock and hp-ux

Since you want to make modification, you must know why you modify it.
Is IO really the bottleneck of your database?If yes, then tune it, if not , why bother tune it?

Sun has Concurrent DIrect IO which solve the single write lock, and AIX has CIO also solved this problem.

Wonder whether HP will also have a release of such support.Since now HP by default used vxfs, I think Veritas will not release such a product which will compete with QuickIO.