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HPSS Performance study

Updated on Mon, 2006-10-30 18:39. Originally created by jeromel on 2006-10-29 07:48. Under:

Introduction

HPSS is software that manages petabytes of data on disk and robotic tape libraries. We will discuss in this section our observations as per the efficiency of accessing files in STAR as per a snapshot of the 2006 situation. It is clear that IO opptimizations has several components amongst which:
  • Access pattern optimization (request ordering, ...)
  • Optimization based on tape drive and technology capabilities
  • Miscellaneous technology considerations
    (cards, interface, firmware and driver, RAID, disks, ...)
  • HPSS disk cache optimizations
  • COS and/or PVR optimization
However, several trend have already been the object of past research and we will point to some of those and compare to our situation rather than debating the obvious. Wewill try to keep a focus on measurements in our environment.

Tape drive and technology capabilities

A starting point would be to discuss the capabilities of the technologies involved and their maximum performance and limitations. In STAR, two technologies remain as per 1006/10:
  • the 994B drives
  • the LTO-3 drives

Access pattern optimization (request ordering, ...)

A first simple and immediate consideration is to minimize tape mount and dismount operations, causing latencies and therefore performance drops. Since we use the DataCarousel for most restore operations, let's summarize its features.

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Phi meson spin alignment wrt production plane / Global polarization of Lambda hyperons

Updated on Mon, 2006-11-06 15:42. Originally created by seluzhen on 2006-10-28 16:19.

Reference

Speaker : Ilya Selyuzhenkov ( WSU )


Talk time : 12:00, Duration : 00:30

Spin Alignment of vector mesons (K*, phi) in Au+Au collisions

Updated on Fri, 2006-11-03 20:54. Originally created by bedanga on 2006-10-28 16:18.

Reference

Speaker : Jinhui


Talk time : 11:30, Duration : 00:30

TEA BREAK

Updated on Sat, 2006-10-28 16:17. Originally created by bedanga on 2006-10-28 16:17.

Reference


Talk time : 11:00, Duration : 00:30

3-particle correlations

Updated on Sat, 2006-10-28 16:16. Originally created by bedanga on 2006-10-28 16:16.

Reference

Speaker : Jason


Talk time : 10:30, Duration : 00:30

3-particle correlations : Is there a Mach cone ?

Updated on Sat, 2006-10-28 16:15. Originally created by bedanga on 2006-10-28 16:15.

Reference

Speaker : Claude


Talk time : 10:00, Duration : 00:30

Probing small-x gluons and large-x quarks: jet-like correlations between forward- and jet-like correlations

Updated on Fri, 2006-11-03 20:42. Originally created by bedanga on 2006-10-28 16:14.

Reference

Speaker : Levente


Talk time : 09:30, Duration : 00:30

Low- and intermediate-pT azimuthal di-hadron correlations

Updated on Sat, 2006-10-28 16:13. Originally created by bedanga on 2006-10-28 16:13.

Reference

Speaker : Mark


Talk time : 09:00, Duration : 00:30

Phi analysis in CuCu collisions

Updated on Tue, 2006-11-07 00:44. Originally created by bedanga on 2006-10-28 15:59.

Reference

Speaker : Xinghua and Bedanga


Talk time : 18:00, Duration : 00:30

Recent multiplicity results from PMD

Updated on Tue, 2006-11-07 00:41. Originally created by bedanga on 2006-10-28 15:57.

Reference

Speaker : Monika


Talk time : 17:30, Duration : 00:30

K* analysis in Au+Au collisions

Updated on Sat, 2006-10-28 15:55. Originally created by bedanga on 2006-10-28 15:55.

Reference

Speaker : Xin


Talk time : 16:30, Duration : 00:30

Scaling of charm integrated cross section and modification of its transverse momentum spectra in d+Au and Au+Au collisions

Updated on Fri, 2006-11-03 20:51. Originally created by bedanga on 2006-10-28 15:54.

Reference

Speaker : Chen


Talk time : 16:00, Duration : 00:30

TEA BREAK

Updated on Sat, 2006-10-28 15:52. Originally created by bedanga on 2006-10-28 15:52.

Reference


Talk time : 15:30, Duration : 00:30

Properties of particle production at large transverse momentum in Au+Au and Cu+Cu collisions at RHIC

Updated on Fri, 2006-11-03 20:40. Originally created by bedanga on 2006-10-28 15:51.

Reference

Speaker : Bedanga


Talk time : 15:00, Duration : 00:30

Yields and elliptic flow of d(dbar) and He3 (He3bar) in Au+Au collisions at sqrt_s = 200 GeV

Updated on Fri, 2006-11-03 20:44. Originally created by bedanga on 2006-10-28 15:49.

Reference

Speaker : Haidong


Talk time : 14:30, Duration : 00:30

A measurement of the centrality dependence of the N(Omega)/N(Phi ratios and Phi anisotropic flow

Updated on Tue, 2006-11-07 03:17. Originally created by bedanga on 2006-10-28 15:47.

Reference

Speaker : Sarah


Talk time : 14:00, Duration : 00:30

AOB

Updated on Fri, 2006-10-27 10:33. Originally created by testadmin on 2006-10-27 10:30.

Reference

Speaker : All ( All )


Talk time : 15:00, Duration : 00:10

IRMIS progress

Updated on Fri, 2006-10-27 10:30. Originally created by testadmin on 2006-10-27 10:28.

Reference

Speaker : Jiro Fujita ( Creighton )


Talk time : 14:50, Duration : 00:10

SDAS enclave reminder (for this year)

Updated on Fri, 2006-10-27 10:27. Originally created by testadmin on 2006-10-27 10:27.

Reference

Speaker : Jerome Lauret ( BNL )


Talk time : 14:30, Duration : 00:10

Opened discussion - BNL domain and SMS / operational needs & requirements

Updated on Fri, 2006-10-27 10:28. Originally created by testadmin on 2006-10-27 10:27.

Reference

Speaker : All ( All )


Talk time : 14:40, Duration : 00:10