# Presentation: 849491

## NPP Science Data Segment (SDS)Data Depository and Distribution Element (SD3E)Delta Design Review for CERESAugust 26, 2008NASA GSFCB8 Auditorium

- 	Evelyn Ho			         Ryan Gerard
-             _[Evelyn.L.Ho@nasa.gov](mailto:Evelyn.L.Ho@nasa.gov)_      	    _[Ryan.Gerard@nasa.gov](mailto:Ryan.Gerard@nasa.gov)_

## SD3E Overview (1 of 2)

- RDR, SDR
- EDR, IP

- RDR, SDR
- EDR, IP

- RDR, SDR,
- EDR, IP

- CERES RDRs

- 32 Day Data Buffer for RDR, SDR, EDR,
- and 5 days of  Retained Intermediate Products

## SD3E Overview (2 of 2)

- SD3E – SDS Data Delivery & Depository Element
- Performs data request and acquisition from major data providers
- Acquires data from NOAA/CLASS, NSIPS, and NESDIS/IDPS
- Now will handle CERES RDRs like other RDRs
- Provides ~32 days “rolling storage” for pick-up by PEATEs and the NICSE
- No data processing of NPP products
- No reformatting
- No aggregation
- No subsetting

## SD3E Level 3 Requirements

- Acquire products [Req. 3.1.1.1 – 3.1.1.18]
- RDRs from IDPS
- xDRs, selected IPs, operational algorithms and source code,  software and documentation, calibration products, selected IPs, and official ancillary/auxiliary data from ADS
- Retained IPs from NSIPS
- Verify data integrity [Req. 3.1.2.1]
- Manage data requests from PEATEs/NICSE [Req. 3.1.3.1 – 3.1.3.10]
- Provide data access to the PEATEs/NICSE [Req. 3.1.4.4]
- Manage 32-day (TBD) data store [Req. 3.1.4.1 – 3.1.4.3]
- Respond to PSOE management direction and provide status reports [Req. 3.1.4.5 – 3.1.4.6]
- General Requirements [Req. 3.6.1 - 3.6.2, 3.6.7, 3.7.1 - 3.8.3.1]

## SD3E Level 3 Requirements for CERES

| Requirement Number | L3 Requirement Covering CERES |
| --- | --- |
| 3.1.1.3 | The SD3E shall be capable of requesting and accepting all RDRs generated by the IDPS. |
| 3.1.1.9 | The SD3E shall be capable of requesting and ingesting xDRs (RDRs, SDRs, EDRs, and TDRs) from the ADS. |
| 3.1.4.3 | The SD3E shall have the capability of providing 32 days of storage to store xDRs and 7 days of storage for all other products (e.g., intermediate products, ancillary data, operational algorithms, calibration products). |
| 3.1.2.1 | The SD3E shall have the capability of validating all the ingested data files based on data delivery reports, digital signature, checksum or other means, ensuring data transfer was done correctly. |

## Context Data Flow Diagram

- NSIPS

- PSOE

## Level 1 Data Flow Diagram

- SD3E

- LAND
- PEATE

- Data Subscription

- NESDIS IDPS

- ASDC

- SDS

- All RDRs

- NOAA CLASS

- NSIPS

- Selected SDR ,IPs
- EDRs, and TDR

- RIPS

**Telemetry RDR, **
**Science RDR, **
**Diagnostic RDR**
**VIIRS SDRs Channels,**
**	****5,7,9, 10-16**
**Aerosol EDR**

**Telemetry RDR (HDF-5)**
**Science RDR, (HDF-5) **
**Diagnostic RDR  (HDF-5)**
**VIIRS SDRs Channels,**
**	****5,7,9, 10-16 (Subsetted HDF4)**
**Aerosol EDR (HDF4)**

## Gap Analysis

- Add CERES product types to SD3E product definition table
- CERES science RDRs
- CERES diagnostic RDRs
- CERES telemetry RDRs
- Additional Data Volume/Disk Space
- Ingest additional 2500.48 KiB/Day (2083.74 KiB/Day + 20% HDF overhead)
- ~78.14 MiB storage for 32 days

## Results of RMA and Throughput Study

- SDS Level 3 Requirement
- 3.7.3 Availability
- The NPP SDS shall have an Operational Availability, Ao., of 0.95.
- Background:  The SDS and associated elements have only been “Research Grade”.
- Risk:  Data latency when the SD3E system is down.
- Will the current requirement be sufficient in meeting CERES requirements?

## Results of RMA and Throughput Study 

- Assumptions
- Five year mission: 43800 hours
- Operating time: 10000 hours
- Time to repair disks: 288 hours (2 weeks)
- Average time for maintenance/resolve problems: 168 hours (1 week)
- Average time to bring system back up (Nominal scenario): 50 minutes
- Time for operator to notice problem: 5 minutes
- Time to take down the system/clean up: 25 minutes
- Time to bring DB back up: 10 minutes
- Time to bring SD3E back up: 10 minutes

## Single Disk Metrics

- P (single disk fails during mission)
- 	= # of hours of mission / MTBF of disk
- 	= 43800 hr / 1000000 hr
- 	= .0438 = 4.4 %
- P(single disk is **down** at a given moment in time during Mission)
- 	= P(single disk fails during mission) x P(disk has not yet been replaced)
- 	= .0438 x (288hr / 43800) = .000288 = .028%
- 				      assumes 2 weeks to repair drive

## Tier Metrics (1 of 2)

- Assumptions:
- disks are placed in tiers of size 10
- 2 or more disks must fail in the same tier for downtime to occur
- P( no disks are down in a given tier)
- =	 P(disk 1 never goes down) * P(disk 2 never goes down) * ... * P(#10 never does down)
- = (.9997)10 = .997

## Tier Metrics (2 of 2)

- P(1 disk is down in a tier)
- = P(disk 1 is Down) x P(disks 2...10 are Up) x # of variations of which disk is down
- = (.000288)(.9997)10(10) = .0029
- P(2 or more disks are down in a tier)
- = 1 – P(no disks are down) – P(1 disk is down)
- = 1 - .997 - .0029
- = .0001

## Whole System Disk Metrics

- P(2 or more disks are down in ANY tier)
- 	= # of tiers x P(2 or more disks fail in a single tier)
- 	= (50)(.0001)
- 	= .005
- Availability = 1 – P(2 or more disks are down in ANY tier)
- Ao of entire disk array = 0.995

## Results of RMA and Throughput Study

| Block | Description | MTBF | Failure/Hour | % time it will Fail |
| --- | --- | --- | --- | --- |
| DB1 (Primary Database server) | Dell PowerEdge 2850 | 84400 | 9.66184E-06 | 0.002 |
| DB2 (Secondary Database server) | Dell PowerEdge 2650 | 103500 | 1.18483E-05 | 0.002 |
| S1 (Primary ingest server) | Dell PowerEdge 2950 | 102100 | 9.79432E-06 | 0.002 |
| S2 (Failover ingest server) | Dell PowerEdge 2950 | 102100 | 9.79432E-06 | 0.002 |
| S3 (Secondary ingest server) | Dell PowerEdge 2950 | 102100 | 9.79432E-06 | 0.002 |
| C1 (Primary Controller 1) | DDN S2A9900 | 56402 | 1.77299E-05 | 0.003 |
| C2 (Secondary Controller 2) | DDN S2A9900 | 56402 | 1.77299E-05 | 0.003 |
| D1 (RAID System) | 500 GB and 1TB 7200 RPM SATA RAID 6 drives | 1000000 per disk | 0.000001 | 0.0002 |

## Results of RMA and Throughput Study

- System Reliability =
- 	[(DB1+DB2-(DB1)(DB2)] * [S1+S2-(S1)(S2)] * S3 * [C1+C2-(C1)(C2)] * D1
- = 0.00702
- = 1 - 0.00702
- = 0.99298

- Operational Availability =
- Where:
- Configuration MTBF = 11447.8 hours
- Mean Time Between Maintenance (MTBM) = 10000 hours
- Mean Down Time (MDT) = 168 hours
- Average down-time events over 10000 hours = 0.8735
- Average down time = 146.75 hours
- Ao = 10000/(10000+146.75)
- Ao = 0.9855

## Throughput Estimates

- Demonstrated Performance:
- Ingest Rate: 4.05-4.4 TB/day
- Tests ranged between 102660 – 146064 files
- Files Ranged in Size Between 500K-300MB
- Tested while 2 simultaneous FTP pulls (simulates the PEATEs)
- Hardware
- Single Disk Controller (S2A8000)
- 2 Dell Servers (2650/2850)

## Throughput Estimates

- Throughput Estimate: 8-12 TB per day
- Rationale: Our memory and CPU averaged at approximately 95% during our throughput tests. Also, our Disk Usage was near 90%. Our next hardware addresses these with:
- 4 high performance servers(each with quad cores)
- Dedicated database servers
- 2 Disk Controllers (with 3 times the performance of our current disk controller)

## Nominal Latency

## Build 3 Plans

- Add CERES RDRs products to SD3E product definition table
- Obtain sample CERES RDR products to test transfer, ingest, verify, and store
- Test interfaces between IDPS/ADS to SD3E to Land to CERES

## Build 4 Plans

- Continue testing interfaces between NESDIS IDPS to SD3E to Land PEATE to CERES
- Continue performance and throughput testing from SD3E to Land PEATE to CERES

## SD3E Capabilities by NCT3

- Receive subscription and ad-hoc requests via Web Interface and machine-to-machine interface
- Coalesce subscriptions from PEATEs/NICSE
- Determine missing products
- Determine products for reorder
- Submit product request using DDS GUI to mini-IDPS
- Ingest, verify, store xDR, ancillary/auxiliary, IPs, and calibration products
- Ingest, verify, store CEREs RDRs
- Notify operator of products for manual reorder
- Operator GUIs to monitor system status and resources
- Report generation capability
- Database replication
- Ingest of RDR Packaged Filenaming (Primary Products ID first)
- Work-around to ingest RDR Packaged Filenaming (sorted product IDs)

## Schedule

- Build 3 delivery 11/05/08
- Handle CERES RDRs
- Handle RDR packaging file naming (including work around)
- Build 3 I&T 11/06/08 - 11/21/08
- Hardware Augmentation Part 1 08/01/08
- Regression Testing 12/22/08 - 01/09/09
- Performance Testing 11/04/08 - 11/18/08
- Build 4  11/06/08 - 12/01/09
- NCT3 06/09/09 - 06/15/09

## Issues/Concerns

- No Issues/Concerns

## Backup

## SD3E-Land-CERES DFD

## CERES RDR Sizing Estimates

| CERES RDR | File Size | Size + 20% HDF5 Overhead |
| --- | --- | --- |
| Science | 1370.84 KiB | 1645 KiB |
| Diagnostic | 685.45 KiB | 822.54 KiB |
| Telemetry | 27.45 KiB | 32.94 KiB |
| Total: | 2083.74 KiB | 2500.48 KiB |