delaylog-------what is this

[Kirk Reindl]

Hi:

I've been trying to find info on what the delaylog parameter does when placed in /etc/fstab.

For instance:

/dev/vgdss1/orasw /orasw vxfs delaylog 0 2

I tried doing a "#man -k delaylog" to figure it out but it is almost like it doesn't exist.

Thanks

Kirk Reindl

[James R. Ferguson · Accepted solution]

Hi Kirk:

'delaylog' and other VxFS (JFS) mount options are documented in the man pages (1M) for 'mount_vxfs'.

"In delaylog mode, some system calls return before the intent log is written. This improves the performance of the system, but some changes are not guaranteed until a short time later when the intent log is written."

Technical Knowledge Base document #KBRC00007737 also offers an explanation (see attached).

Attachment deleted as per ITRC Guidelines

Regards!

...JRF...

[Christopher McCray_1]

I believe that it means "delay" writing metadata information to the intent log used by vxfs for file system recovery until a sync command is issued from the system.


Hope I've steered you in the right direction.

Chris

[Uday_S_Ankolekar]

Check this link on docs.hp.com
http://www.docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B3929-90011/B3929-90011_top.html&con=/hpux/onlinedocs/B3929-90011/00/00/46-con.html&toc=/hpux/onlinedocs/B3929-90011/00/00/46-toc.html&searchterms=delaylog&queryid=20011206-114220
-USA..

[Sanjay_6]

Hi Kirk,

try this link,

http://us-support2.external.hp.com/cki/bin/doc.pl/sid=0d75e08f18c76472d1/screen=ckiDisplayDocument?docId=200000048194462

Hope this helps.

Regds

[Sridhar Bhaskarla]

Hi Kirk,

Normally I/O is written to the inodes and then the intent log is updated unlike hfs. With delaylog mount option, the acknowledgement comes back sometimes before the intent log is updated so that the process doesn't have to wait for I/O to complete.

-Sri

[Deshpande Prashant]

Hi

Following link explains the different mount options
Document Id : KBAN00000258

http://us-support2.external.hp.com/cki/bin/doc.pl/sid=42153c7d027b067f97/screen=ckiSearchResults?searchString=KBAN00000258&mode=id

Thanks.
Prashant.