HP-UX HB v13.00 Ch-14 - JFS

HP-UX Handbook – Rev 13.00 Page 43 (of 47)

Chapter 14 Journaled File System (JFS)

October 29, 2013

Intent Log <specific options>

log all metadata changes are logged immediately (default)

delaylog only critical metadata changes are logged immediately

tmplog metadata changes logging is almost always delayed

nolog intend log is disabled

Write <specific_options>

direct direct writes

dsync datasynchronous writes

closesync sync on close writes

tmpcache temporary caching

Further there is the possibility to determine how ordinary/synchronous writes are treated

(only for Online JFS):

mincache = direct|dsync|closesync|tmpcache ordinary writes

convosync = direct|dsync|closesync|tmpcache synchronous writes

Other <specific_options>

blkclear all data extents are cleared before being allocated to a files

Displaying File System Features

There are two commands available to display the file system features ,for example to check the

disk layout or if the file system supports large files.

The mkfs – m command displays the command line which created the file system.

Examples:

# mkfs –m /dev/vgXX/lvolY

# mkfs -m /dev/vg00/lvol5

# mkfs -F vxfs -o ninode=unlimited,bsize=1024,version=4,inosize=256,logsize=1024,largefiles

/dev/vg00/lvol5 20480

The fstyp –v command displays the contents of the superblock

Examples :

# fstyp –v /dev/vgXX/rlvolY

# fstyp -v /dev/vg00/rlvol5

vxfs

version: 4

f_bsize: 8192

f_frsize: 1024

f_blocks: 20480

f_bfree: 18625

f_bavail: 17717