1 / 7

POOL in LHCb

POOL in LHCb . Packages used Plans. Packages in use. StorageSvc RootStorageSvc Directly used from Gaudi conversion service Catalog (xml) in Gaudi with POOL format. Plans. We are unhappy using POOL Not the most efficient use of ROOT

ebony
Download Presentation

POOL in LHCb

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. POOL in LHCb Packages used Plans November 2010

  2. Packages in use • StorageSvc • RootStorageSvc • Directly used from Gaudi conversion service • Catalog (xml) in Gaudi with POOL format November 2010

  3. Plans • We are unhappy using POOL • Not the most efficient use of ROOT • Complicated to modify things, which do not meet thePOOL model: domain->database->container->object • No need anymore to isolate event persistency from ROOT • The I/O war is over: ROOT won • Gaudi persistency is already an isolation layer • Why keep several call stack for something no longer worth it ? November 2010

  4. Plans • Plan is to retire POOL • “Not before the next big shutdown” • My claim: Won’t happen: if, the migration should ~ start nowIt takes some time until all production stuff is tested • So ??? • Clearly I want LHCb to change • POOL maintenance at minimum November 2010

  5. POOL Replacement • Implementation ready • Developed to test/measure performance of the TTree caches in ROOT • Direct use of ROOT from Gaudi conversion service • Change of paradigm: • Fat trees with many branches • 1 Tree for all event data • Reference mechanism preserved for Gaudi refs • Reading of POOL files written by LHCb possible November 2010

  6. LHCb IO Example: Elapsed Time November 2010

  7. CPU Consumption: Better utilization November 2010

More Related