• Amazon,  AWS,  I/O,  Logs,  S3,  Storage

    Collecting S3 Access Logs

    September 25, 2018

    Amazon allows you to enable S3 access logging that you can use to monitor S3 performance: request rate, I/O workload, user and compute node level statistics, service delays and outages, and much more.

    S3 log files are quite small, uncompressed text files that in case of intensive S3 usage can be generated almost every second:

    ...
2018-09-20 16:20:27     323567 2018-09-20-16-20-26-DE17FAE504462084
2018-09-20 16:20:28     598192 2018-09-20-16-20-27-5F17C98DFA22DA31
2018-09-20 16:20:29     618862 2018-09-20-16-20-28-4660E2CBCB0FB2C5
2018-09-20 16:20:32     381675 2018-09-20-16-20-31-16549B7BABDA06AE
2018-09-20 16:20:33     405131 2018-09-20-16-20-32-14AB46312C254397
2018-09-20 16:20:34     587042 2018-09-20-16-20-33-385E799AFCEBAEE3
2018-09-20 16:20:35     358275 2018-09-20-16-20-34-FA52E601A410E529
2018-09-20 16:20:36     604080 2018-09-20-16-20-35-C02066EDF9026EF9
...

    So you can have 35K+ files generated per day (and there is no a sub-directory for each day), and if you are going to analyze S3 statistics for a long period of time (weeks, months), the performance of your Hive or Presto queries can be very low.

    Additionally there is often a lifecycle rule defined to keep logs only for 1-2 days.

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