Compare FFmpeg with Elastic Transcoder (performance + pricing)

[danillouz]

I used a 3 minute audio recording (WebM) of 1.1MB to trigger some transcoding jobs.

[danillouz]

AWS Elastic Transcoder

AWS outputs the transcoding time in the console.

Run	Time
1	6,185 sec
2	6,211 sec
3	6,877 sec

[danillouz]

FFmpeg + Lambda

Used the CloudWatch logs to extract the Lambda execution time, while using different Lambda memory configurations:

128 MB

Run	Duration	Billed duration
1	38,333 ms	38,400 ms
2	38,019 ms	38,100 ms
3	37,102 ms	37,100 ms

256 MB

Run	Duration	Billed duration
1	20,530 ms	20,600 ms
2	19,113 ms	19,200 ms
3	18,992 ms	19,000 ms

512 MB

Run	Duration	Billed duration
1	10,017 ms	10,100 ms
2	9,351 ms	9,400 ms
3	9,312 ms	9,400 ms

1024 MB

Run	Duration	Billed duration
1	4,912 ms	5,000 ms
2	4,763 ms	4,800 ms
3	4,611 ms	4,700 ms

2048 MB

Run	Duration	Billed duration
1	2,890 ms	2,900 ms
2	2,705 ms	2,800 ms
3	2,679 ms	2,700 ms

3008 MB (max)

Run	Duration	Billed duration
1	2,828 ms	2,900 ms
2	2,485 ms	2,500 ms
3	2,608 ms	2,700 ms

[danillouz]

These are not very extensive benchmarks, but IMHO good enough to see the trend where transcoding audio becomes twice as fast, while doubling Lambda memory, up to 2 GB.

This means the best memory setting for the FFmpeg Lambda is 2048 MB.

[danillouz]

AWS Elastic Transcoder

In terms of costs, AWS Elastic Transcoder is quite expensive (compared to Lambda).

For EU Ireland, we pay $0,00522 per minute of transcoded audio. Where we get 20 minutes for free every month in the free tier.

Note that the AWS Elastic Transcoder pipeline and S3 buckets have to be in the same region to avoid data transfer costs.

Cost example

To transcode 100 000 audio files of 3 minutes each, takes: 100 000 * 6.4 sec avg transcoding time = 640 000 sec = 10666,666666667 min transcoding time

$0,00 522 * 10666,666666667 = $55,68

[danillouz]

FFmpeg + Lambda

For Lambda, the cost depends on the memory setting and execution duration (GB/s).

For EU Ireland 1 GB/sec costs $0,000 00 1667.

Note that since the S3 buckets and Lambdas run in the same region, we avoid (S3) data transfer costs.

Cost example

To transcode 100 000 audio files of 3 minutes each we pay:

• The average runtime for a 2048 MB Lambda is 3 sec (worst case, rounded up)
• 100 000 audio files of 3 minutes is 100 000 * 3 sec runtime = 300 000 sec execution duration
• Compute: 2048 MB / 1024 MB * 300 000 sec = 600 000 GB/sec

Without free tier we pay: 600 000 GB/sec $0,000 00 1667 GB/sec = $1,0002 (holy sht!) (With free tier we pay: 600 000 - 400 000 GB/sec * $0,000 00 1667 GB/sec =  $0,3334)

😅💰💪