Limit our investment in SAS capacity

urn:js:virtue:aspire:proposal:26.1

TL;DR

Limit our investment in SAS capacity

Rational

The current SAS environment for EDW is a grid with 3 nodes. Utilisation of this environment reaches 80% today, so there is limited headroom & parallel running EDWS and EDW is likely to result in performance issues for users.

SAS provided a quote to provide additional perpetual licenses for parallel run that we could retain on-going for an enduring Dev/Test environment. This is best practice, and the absence of a Dev environment does cause us difficulty. However, the costs are prohibitive (initial quote was close to £0.5m!)

• We are exploring an option to sweat our existing asset by splitting the current grid, giving EDW 2 nodes (down from 3). One node will be dedicated to batch (out of hours) and during the day, users will have access to the two nodes. We would make this change in Sept, to test the kind of experience given to users and monitor their feedback. We would also like SAS to give us a quote for additional cores that we could lease form them from a period (e.g. to increase the machine specs from 10 cores to 12).

We will then dedicated the third node to EDWS. As the full SAS user estate will not be using the system is heavily during parallel run, we hope this will be an acceptable compromise. Again, we would like SAS to provide a quote for a temporary lease of additional capacity.

After the parallel run, EDWS would return to the 3 node cluster we have today, with the current run costs. This does NOT address the absence of an enduring Dev/Test environment, but it does contain our costs.

Outcome

Agreed that we want to minimise our investment with SAS, and we should invest first in tuning current usage profile.

Agreed that we can reduce the capacity in SAS nodes and assess impact on performance from 3rd Sept. Note: business likely to be most sensitive about the Trade Driving scripts, so we should closely monitor impact on them.

Implications

None.

Appendix

Migrated From Confluence

link Original Author : Brett Mackay