EFS Performance Calculator
Model EFS bursting credits: baseline throughput, burst ceiling and how long the credit bucket lasts under load.
About EFS Performance Calculator
In Bursting mode an EFS file system earns throughput from the bytes it stores: 50 KiB/s of baseline per GiB, with a credit bucket that lets it run far above that until the credits are gone. Any demand above baseline drains the bucket at exactly the excess rate, so a small file system driving heavy throughput has a runway measured in hours, then collapses to baseline. Buying only the excess as Provisioned Throughput is what turns that cliff into a flat, predictable rate — priced here from a user-supplied list price to confirm on the AWS EFS pricing page for your region. Almost every EFS performance incident is a drained credit bucket rather than a broken workload, and the runway figure tells you how many hours of a batch window you have before the file system throttles.
Formula
EFS Performance
baseline MiB/s = GiB x 50 KiB/s ÷ 1024; burst runway hours = credit bucket in MiB ÷ ((demand − baseline) x 3600).
- credit bucket
- MiB of burst credit held, sized from the TiB stored
- drain
- Demand above baseline, the rate credits are consumed
Worked example
With the default values below, EFS Performance Calculator returns Burst Runway of 15.3 hours of burst before the credit bucket empties. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Standard-tier data in the file systemminimum 0 GiB
- 2,048 GiB
- Baseline throughput earned per GiBminimum 0 KiB/s per GiB
- 50 KiB/s per GiB
- Burst throughput per TiBminimum 0 MiB/s per TiB
- 100 MiB/s per TiB
- Credit bucket size per TiB storedminimum 0 TiB per TiB
- 2.1 TiB per TiB
- Sustained throughput the workload drivesminimum 0 MiB/s
- 180 MiB/s
- Provisioned throughput priceminimum 0 USD per MiB/s-month
- 6 USD per MiB/s-month
Results
- Burst Runway
- 15.3 hours of burst before the credit bucket empties
- Baseline Throughput
- 100.00 MiB/s
- Burst Throughput Ceiling
- 200.00 MiB/s
- Hours of Burst Available
- 15.3 hours
- Provisioned Throughput to Buy
- 80.00 MiB/s
- Provisioned Throughput Cost
- $480.00
Step by step
- 1Values used
- 2EFS Performance
- 3Burst Runway= 15.3 hours of burst before the credit bucket empties
- 4Baseline Throughput= 100.00 MiB/s
- 5Burst Throughput Ceiling= 200.00 MiB/s
- 6Hours of Burst Available= 15.3 hours
- 7Provisioned Throughput to Buy= 80.00 MiB/s
- 8Provisioned Throughput Cost= 480.00
Assumptions and limits
- The result is derived only from the 6 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is EFS Performance calculated?
baseline MiB/s = GiB x 50 KiB/s ÷ 1024; burst runway hours = credit bucket in MiB ÷ ((demand − baseline) x 3600). In Bursting mode an EFS file system earns throughput from the bytes it stores: 50 KiB/s of baseline per GiB, with a credit bucket that lets it run far above that until the credits are gone. Any demand above baseline drains the bucket at exactly the excess rate, so a small file system driving heavy throughput has a runway measured in hours, then collapses to baseline. Buying only the excess as Provisioned Throughput is what turns that cliff into a flat, predictable rate — priced here from a user-supplied list price to confirm on the AWS EFS pricing page for your region.
Why does EFS Performance matter?
Almost every EFS performance incident is a drained credit bucket rather than a broken workload, and the runway figure tells you how many hours of a batch window you have before the file system throttles.
What values do I need to enter?
This calculator takes 6 inputs: Standard-tier data in the file system, Baseline throughput earned per GiB, Burst throughput per TiB, Credit bucket size per TiB stored, Sustained throughput the workload drives, Provisioned throughput price. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.
Is Elastic throughput better than Bursting?
Elastic removes the credit model entirely and bills per GB read and written, which suits spiky, unpredictable workloads. Bursting is cheaper for steady access that fits inside the baseline the stored data already earns.