VXFS tuning

[system administrator_15]

I know i can tune hfs through tunefs script. but what about vxfs, is there a tunefs script for that or is it only done through fstab.

[Tonya Underwood]

vxtunefs is probably the command you are looking for!

Hope this helps!
Tonya Underwood

[Geoff Wild]

Also look at fsadm - can be used to defrag vxfs:

fsadm -F vxfs -d -D -e -E /mountpoint

Also look at this doc - in particular the section "VxFS Performance: Creating, Mounting, and Tuning File Systems"

http://docs.hp.com/hpux/onlinedocs/5971-4772/5971-4772.html

Rgds...Geoff

[system administrator_15]

thanks for the info, i am trying to change perameters for my test box and have tried the following command, it seems to not like it does the file tunefstab need to be created first or does the command line entry do it automatically.
i am trying

vxtunefs -ps -f -o read_nstream=2 /u01
am i having an OAP moment.
thanks

[Tonya Underwood]

The file is not necessary as far as I can tell.

However you are specifying -f... this means that you are telling it the file to use. However in your command I do not see the file. Try leaving the -f option off.

Tonya Underwood

[system administrator_15]

tried leaving -f off no difference ouput as below

vxtunefs -ps -o read_nstream=2 /u01
vxfs vxtunefs: Usage:
vxtunefs [-p] [-s [ -f tunefstab ] [ -o options ]]
[mount point | special ] ...

where options is a comma separated list of one or more of the following:

[read_pref_io=value],
[read_nstream=value],
[read_unit_io=value],
[write_pref_io=value],
[write_nstream=value],
[write_unit_io=value],
[pref_strength=value],
[buf_breakup_sz=value],
[discovered_direct_iosz=value],
[max_direct_iosz=value],
[qio_cache_enable=value],
[max_diskq=value],
[initial_extent_size=value],
[max_seqio_extent_size=value],
[default_indir_size=value],
[max_buf_data_size=value]

-o and -f options are mutually exclusive
The default tunefstab is /etc/vx/tunefstab
regards

[Nicholas Melville]

Try using only the -s switch as the -p is only used to print the parameters.

Good luck,
Nicholas

[avsrini · Accepted solution]

Hi Andy,

for tuning mounted vxfs filesystem use
vxtunefs command

#vxtunefs -s -o read_nstream=2 /mountpoint

If filesystem is unmounted and remounted, this
value will be reset.


To make the changes persistent upon remounts / reboots
create /etc/vx/tunefstab as follows and modify
the parameters for required filesystems


/dev/vg01/lvol2 read_pref_io=64k
/dev/vg01/lvol2 read_nstream=4

Parameters for system wide also can be set.
This will override values specified for each
filesystems.

system-default read_pref_io=128k

Have fun
Srini