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Decisions required before purchase

Note: Order must be $5,000 or larger to not pay "overhead". Therefore, buy parts, especially small ones, together. (And a single purchase is better than multiple, $5,000+ purchases.)

Decisions made

Compute nodes

NOTE: Must finalize quantity (and final, final specs) after all other decisions are made and priced.

4/14/14. Czarek: It looks like the slowest cpu E5-2620v2 2.1GHz has the best price performance ratio but anyway I would not buy the slowest cpu. Right now in Gdansk we are buying 10 servers and we decided to go for 10-core cpus E5-2670v2 2.5Ghz (20 cores per node). As in matrix in Gdansk we have only slow interconnect between nodes and some programs can run efficiently only on single node so more cores per node gives for such program advantage. Other programs both in Gdansk and on matrix just need the highest possible total performance and exchange very little data between nodes so than number of cores is not important. What about space restriction ? Is it better to buy smaller number of faster nodes ?

 

See also:

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Decisions considered

Decision 1: Storage of users' data

Where should users' data be located?

  • Current answer: Hard drive RAID array in the head node.
  • Choices identified by ChemIT, to work through with Czarek:

Choice to provision users' data storage:

Pro

Con

Notes

Within the head node
(status quo)

Sunk cost: Pay once and it lasts at least through warranty period, probably longer (no monthly costs)
Known technology and proven performance.

May need to over-provision (pay extra up-front), speculating on future demands. Invest more now to reduce downtime due to future upgrade.
Depended on same sub-systems, so off-site backup (such as EZ-Backup) is critically important.

 

SFS

Fee based: Get only what you need.

Fee based: Monthly costs.
Must confirm: Meets Matrix's performance needs?
Includes off-site disaster-recovery backups.
Can include versioning (uses 20% of the space).

Used pervasively in Chemistry research, with versioning turned on for all instances.

NAS

 

Must confirm: Meets Matrix's performance needs?

 

Dedicated, separate file server

 

Oliver not willing to have ChemIT set up and run?

 

Decision 2: Backups

How should Matrix be backed up?

Answer is DEPENDENT on Decision 1.

  • Must include capacity to restore OS, applications and configurations, and users' data.
  • Current answer: Cornell CIT's EZ-Backup.
  • Choices proposed by ChemIT, to work through with Czarek:
    • TBA: Backup may be included in options considered for Decision 1.
      • If still required, ChemIT still recommends EZ-Backup.

Decision 3: Head node specifications

The head node specifications is DEPENDENT on Decision 1 (and maybe Decision 2).

  • Size decision
    • 1U is cheapest, and fine if don't need to hold lots of drives.
    • 2U is more expensive, but can hold more drives.

Considerations for upgrade (info-gathering phase)

  • (with Matrix-specific notes)