Sizing impact

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Load tests on decent hardware have shown a CPU usage increase that is very acceptable. When only trap tool and statistics tool are running a few percent. With performance tool recording SQL statements a little above 5%, but well below 10% increased CPU usage when CPU was 30%, 50% and even 70%.

Memory and disk usage are analysed in the following table per tool

Tool Memory Disk usage
Log Tool Constant and very small because logs immediate to disk About 500.000 records in 1 GB. Protection options rotate by default at 100.000 records.
Trap Tool Constant and small, because only records a predefined amount of data. On trapping a separate thread is outputting. In the rare occasion that a server is generating a huge amount of traps the output queue takes some memory as well. About 500.000 records in 1 GB. Protection options rotate by default at 100.000 records.
Statistics Tool Constant and small because 1 record per microflow Small, for daily 1000 microflows it would mean below 1.000.000 records in 3 years taking say 3 GB. Cleanup options are configure to only keep the last year, or 1 GB in this example.
Performance Tool Can fill up memory if the protections are removed. Hence the protection measure in the tool. In 512 MB you can store 50.000 microflows with on average 8 actions or 40.000 microflows including 50.000 SQL statements 50.000 microflows including actions and relation tables take 450 MB. 50.000 SQL statements take 100 MB (formula is more or less 1 kb per microflow, 1 kb per action, 2 kb per SQL). Usage of the performance tool is seen as on a case by case basis and so should cleanup be done as well. The system can automatically cleanup all traces from older than 1 month.
Measurement Tool A thread per measurement takes a small amount of memory About 1.000.000 measurements in 100MB. Doing the basic measurements for CPU and memory every 5 seconds means around 20.000.000 records a year, or roughly 2 GB.The system can automatically cleanup all traces from older than 1 year.
Advised reservation 512 MB 1 GB