HPSS User Forum Site Report

1
HPSS User Forum - Site Report

• Bill Weeks
• Stanford Linear Accelerator Center
• Produced under contract DE-AC03-76SF00515 between
  Stanford University and the Department of Energy

2
BaBar The B-Factory

• Use big-bang energies to create B meson particles
• Look at collision decay products
• Answer the question where did all the
  anti-matter go?
• 600 physicists collaborating from gt75 sites in 10
  countries
• USA, Canada, China, France, Germany, Italy,
  Norway, Russia, UK, Taiwan
• The experiment produces large quantities of data
• 200 - 400 TBs/year for 10 years
• Heavy computational load
• 262,000 SpecInt95s available in compute farm
• 2539 compute nodes with 4181 cpus

3
BaBar HPSS Software Levels
Date Machine OS DCE Encina HPSS Jul 98
F40 4.1.5 2.1 2.1 3.2 Sep 99
F50 4.2.1 2.1 2.5 4.1 Jan 01
F50 4.3.3 2.2.0.8 4.2.0.14 4.1.1.4 Aug 03
480R 8 3.2.0.4 5.0
4.5.0.1 Jan 05 480R 8
3.2.0.4 5.0 4.5.1.0

• Only change was applying 4.5.1.0 patch
• BaBar operation makes major software upgrades
  difficult

4
BaBar HPSS Bytes Processed per Day
5
BaBar HPSS Total Space Used
6
Public HPSS Software Levels
Date Machine OS DCE Encina HPSS May 01
420R 7 3.1 4.3.0.3 4.2 Dec 01 420R
8 3.1 4.3.0.4
4.3 ?????? 420R 8 3.2.0.4 5.0
4.5.1.0

• No changes for 3.5 years
• Modest activity level

7
Public HPSS Bytes Processed per Day
8
Public HPSS Total Space Used
9
What does the future hold?

• Going it alone with Solaris
• How do we get to HPSS 6.2 system?
• What conversion steps are supported and/or
  tested?
• Solaris movers?
• Use mixed platforms, e.g. Linux core server,
  Solaris DB2
• What versions of Linux are supported on what
  platforms?

10
HPSS Problems

• PVL crash during overwrite label import
• Fixed in 4.5.1.0 patch
• Tape mounting strategy when system over-committed
• Problems with drive selection, unnecessary
  passthru operations
• Tapes on deferred dismount queue not dismounted
  first

11
Summary

• HPSS is reliable
• HPSS tape handling could be improved
• Software upgrades will always be a problem