JFS Logs

[comtec17]

Hello all,
I have always been taught that you create 1 jfs logvol per volume group on the system. What does everyone else here do?

 

[SPguru]

You can have more than 1 log per VG. It all depends on the size of the filesystems in the VG and location of PV in the VG. Also, a log can only be 256MB (1GB of outline log in 5.2) so if the FS is huge then a second log would be needed. General rule is 2MB log space for 1GB of filesystem size.

 

[usige]

On high transaction databases I create multiple logs on seperate disks. Regular low write fs's have no problem with a single shared JFS log, but if you have a number of fs's with a high write ratio I find it better to split the jfs logs. This keeps the JFS log from becomming a hotspot/bottleneck.

 

[sushveer]

Hi
There is one jfslog per one volume group.But depending on the application and busy file system ...better to create one
jfslog per one jfs file system.No problem...no hard and fast rules over here

sushveer
IBM certified specialist-p-series AIX5L System Administration
AIX/SOLARIS/WEBSPHERE-MQ/TIVOLI Administrator

 

[comtec17]

Thanks for all your responses.