Me in IT UNIX/Linux consultancy

i have investigated some time to look at the performance of Solaris with Oracle on it. Here is some information that might be relevant.

maxcontig:
definition: maximum contiguous i/o size

• check:
  (input) # fstype -v /dev/dsk/c0t0d0s0 | grep maxcontig
  (output) maxcontig 128 rotdelay 0ms rps 167
• default:
  (output) maxcontig 128 rotdelay 0ms rps 167
• change:
  for existing filesystem:
  (input) # tunefs -a 256 /dev/dsk/c0t0d0s0
  for new filesystems:
  (input) # newfs -C 256 /dev/rdsk/c0t0d0s0

maxphys:
definition: largest physical i/o operation allowed

• check:
  (input) # adb -k
  (input) maxphys/D
  (output) maxphys: 131072
• default:
  (output) maxphys: 131072
• change:
  add or change in /etc/systems and reboot
  (input) set maxphys 1048576
  when using a metadevices, also set this one same value as "set maxphys value".
  (input) set md:md_maxphys 1048576

directio:
definition: ufs feature to bypass the buffer-chache

• check:
  (input) # mount | grep directio
• default:
  not enabled.
• change:
  change options in /etc/vfstab and reboot:
  (input) /dev/md/dsk/d0 /dev/md/rdsk/d0 / ufs 1 no logging
  directio
  or manually mount the filesystem:
  (input) mount -o directio /dev/md/dsk/d0 /

tcp_time_wait_interval
definition: the time in milliseconds a tcp connection stays in time_wait state

• check:
  (input) # ndd /dev/tcp tcp_time_wait_interval
  (output) 240000
• default on solaris 8 systems:
  (output) 240000
  default on solaris 9 systems:
  (output) 60000
• change:
  (input) # ndd /dev/tcp -set tcp_time_wait_interval 60000\r\n