Einstein@Home Server Infrastructure at AEI Hannover

Overview

The Einstein@Home servers at AEI Hannover are used in two different contexts:

• The Arecibo Binary Pulsar Search (ABP, part of the Einstein@Home Project)
• Replication and backup of the production database at UWM

Current setup and data flow for ABP

einstein-dl.aei.uni-hannover.de

• Operating system: Debian 4.0 (Etch)
• Features the usual BOINC project directory (like einstein.phys.uwm.edu): /BOINC/projects/EinsteinAtHome
• Runs the following daemons
  • ABP workunit generator (up to three concurrent instances, memory-bound)
    • Input data files are preprocessed on orion and then moved to /BOINC/projects/EinsteinAtHome/input_raw
    • During workunit generation...
      • the pre-processed input files are first moved to /BOINC/projects/EinsteinAtHome/input_files
      • the pre-processed input files are then removed again from /BOINC/projects/EinsteinAtHome/input_files (when done)
      • the final output files are moved to /BOINC/projects/EinsteinAtHome/download (into 1024 subdirectories)
  • ABP validator
  • ABP assimilator
    • Stores the uploaded result files in /BOINC/projects/ABPx (using hardlinks to/of file in /BOINC/projects/EinsteinAtHome/upload)
    • The result files are collected in gzipped tarballs on a daily base in: /BOINC/projects/ABPx/tarballs/[MONTH]
    • The result tarballs are stored on a separate server: backup
  • ABP file deleter
  • Apache
    • Download of ABP data (not applications) from: /BOINC/projects/EinsteinAtHome/download
    • Upload of ABP data (using /BOINC/projects/EinsteinAtHome/cgi-bin/file_upload_handler) to: /BOINC/projects/EinsteinAtHome/upload
    • Acts as a download mirror of einstein.phys.uwm.edu (all applications as well as hierarchical search data) in: /data/BOINC/EatH
• Connected via VPN to einstein-db2.phys.uwm.edu

einstein-db.aei.uni-hannover.de

• Operating system: Debian 5.0.3 (Lenny)
• Used as a replication slave of the Einstein@Home master (production) database
• Installation directory: /data/mysql
• Backups (MySQL dumps) of this replica are created on a daily base
  • Backup directory: /data/mysql/backup
  • Current size of one backup: 2.5 GB (gzipped)
  • Stored on a separate server: backup
• Connected via VPN to einstein-db2.phys.uwm.edu

Planned future setup and data flow for ABP

General idea

• The hardware of einstein-dl.aei.uni-hannover.de will be replaced and the operation system will be upgraded to Debian 5.0.3 (Lenny). This server will hold all data (i.e. all found in /BOINC)
• A new server einstein-wug.aei.uni-hannover.de will be installed to allow for more simultaneous instances of the ABP workunit generator. This server is going to run all project daemons, only the web server be kept on einstein-dl. However, it's local directory /data/BOINC will only be a mountpoint to einstein-dl:/data/BOINC.
• The server einstein-db.aei.uni-hannover.de is not going to be changed

einstein-dl.aei.uni-hannover.de (new)

• Operating system: Debian 5.0.3 (Lenny)
• Holds all BOINC related data in /data/BOINC/projects/EinsteinAtHome (shared with einstein-wug)
• Runs the following daemons:
  • Apache
    • Download of ABP data (not applications) from: /data/BOINC/projects/EinsteinAtHome/download
    • Upload of ABP data (using /data/BOINC/projects/EinsteinAtHome/cgi-bin/file_upload_handler) to: /data/BOINC/projects/EinsteinAtHome/upload
    • Acts as a download mirror of einstein.phys.uwm.edu (all applications as well as hierarchical search data) in: /data/BOINC/mirror

einstein-wug.aei.uni-hannover.de

• Operating system: Debian 5.0.3 (Lenny)
• Is a Nehalem powered 8-core machine (16 logical cores)
• Uses /data/BOINC as a local mountpoint of einstein-dl:/data/BOINC (has no local data)
• Runs the following daemons:
  • ABP workunit generator (up to eight concurrent instances, core-bound)
    • Prepocessing will still be done on orion by Benjamin, resulting files be made available on einstein-wug via NFS (mountpoint /data/BOINC/projects/EinsteinAtHome/input_raw)
    • The workunit generator will make a "local working copy" by moving the respective input file to /data/BOINC/projects/EinsteinAtHome/input_files (as usual)
    • The workunit generator output files will be moved to /data/BOINC/projects/EinsteinAtHome/download (as usual)
  • ABP validator
    • Same rules apply as for the current assimilator setup (see above)
    • Note: upload (data/BOINC/projects/EinsteinAtHome/upload) and assimilation (/data/BOINC/ABPx/) directories use the same relative NFS mountpoint (data/BOINC/) pointing to einstein-dl:/data/BOINC
  • ABP assimilator
    • Same rules apply as for the current assimilator setup (see above)
    • Note: upload (data/BOINC/projects/EinsteinAtHome/upload) and assimilation (/data/BOINC/ABPx/) directories use the same relative NFS mountpoint (data/BOINC/) pointing to einstein-dl:/data/BOINC
  • ABP file deleter
    • Same rules apply as for the current assimilator setup (see above)
    • Note: upload (data/BOINC/projects/EinsteinAtHome/upload) and assimilation (/data/BOINC/ABPx/) directories use the same relative NFS mountpoint (data/BOINC/) pointing to einstein-dl:/data/BOINC
• Connected via VPN to einstein-db2.phys.uwm.edu

Implementation

The TODO list as well as the current status will be maintained in Redmine...

Questions so far:

1. How much disk space is needed on orion?
2. How much disk space is needed on einstein-wug?
3. How many WUs can be served by einstein-dl (in terms of space and CPU/disk drive power)?