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Keystone
3.0

Performance SLO for Keystone

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NetApp Keystone offers latency-based SLO per performance service level, as described in the Keystone order for consumed capacity up to the burst limit, according to the following listed terms and conditions.

Metrics

  • Degraded performance: The amount of time, in minutes, per incident, during which the 90th percentile latency target is not met.

  • The 90th percentile latency is measured per volume, per performance service level instance, for all volumes within a Keystone Order. Latency is sampled every five minutes, and the 90th percentile value calculated over a 24-hour period is used as the daily measure, considering the following points:

    • The volumes that record at least five IOPS at the time of metrics collection are considered for a sample.

    • Volumes with greater than 30% write operations at the time of metrics collection are excluded from the sample.

    • For volumes that have FabricPool enabled, the latency incurred due to the transfer of data to and from the target (cold) storage is not counted.

    • Latency caused by the application, host, or customer network outside of the ONTAP cluster is not counted.

    • During a 24-hour period, at least ten valid metrics should be available. If the condition is not met, the metrics will be discarded.

    • In FabricPool configurations, performance levels are applicable when all requested data blocks are on FabricPool source (hot) storage and the source storage is not in a SnapMirror Synchronous relationship.

Performance service levels

All performance service levels that ONTAP flash storage arrays support are eligible for Performance SLO and guarantee meeting the following target latency:

Service level

Extreme

Premium

Standard

Value

Target 90th percentile latency

<=1ms

<=1ms

<=4ms

>=4ms

To learn more about the latency requirements of the performance service levels, refer to Performance service levels in Keystone.

Service credits

Note SLAs and guarantees are available on a nomination basis.

NetApp issues service credits for the degraded performance:

Performance threshold

Service credit

90th percentile latency > target latency

3% for each calendar day of occurrence

Service credit calculation

Service credits are determined using the following formula:

Service credits = (impacted capacity / total committed capacity) X capacity fees X affected days X credit percentage

Where:

  • impacted capacity: The amount of stored capacity affected.

  • total committed capacity: The committed capacity for the performance service level for the Keystone order.

  • capacity fees: The fees for the affected performance level as per the Keystone order.

  • affected days: The number of calendar days impacted.

  • credit percentage: The predetermined percentage for service credit.

Example

The following example shows the method of calculation for service credits:

Service level

Impacted capacity

Total committed capacity

Capacity fees

Affected calendar days

Credit percentage

Extreme

10 Tib

50 Tib

$1000

2

3%

Using the formula:
Service credits = ( 10 / 50 ) X 1000 x 2 x 0.03

Based on the calculation, the service credits will be $12.

Service credit request

If a breach of the SLA is detected, open a priority 3 (P3) support ticket with NetApp Keystone support.

  • The following details are required:

    1. Keystone subscription number

    2. Volumes and storage controller details

    3. Site, time, date, and description of the issue

    4. Calculated time duration of latency detection

    5. Measurement tools and methods

    6. Any other applicable document

  • Provide the details in the Excel sheet as shown below for a P3 ticket opened with NetApp Keystone support.

    excel sheet template

Note

  • A service credit request should be initiated within six weeks after NetApp Keystone support has validated a breach. All service credits should be acknowledged and approved by NetApp.

  • Service credits might be applied to a future invoice. Service credits do not apply to expired Keystone subscriptions. To learn more, refer to NetApp Keystone support.