Page Comparison

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1. From 10 Parallel request (of 10 sequential request) the client can't always connect and we see time out error (succes ratio <100%)
   1. Sequential request are fired faster than actual responses so from DB perspective they are almost parallel request as well 
2. Database probably already become bottleneck with 2 threads, effectively firening a total of 20 call very quickly. Its know that the DB connection pool/internal will slow down from 12 or more 'parallel' request

Get 1000 nodes in Parallel with varying thread count

In this test, 1000 requests are sent using curl, but with varying thread count (using --parallel-max option).

echo -e "Threads\tTime"
for threads in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 20 30 40 50; do
	echo -n -e "$threads\t"
	/usr/bin/time -f "%e" curl --silent --output /dev/null --fail --show-error \
		--header "Authorization: Basic Y3BzdXNlcjpjcHNyMGNrcyE=" \
		--get "http://localhost:8883/cps/api/v1/dataspaces/openroadm/anchors/owb-msa221-anchor/node?xpath=/openroadm-devices/openroadm-device\[@device-id='C201-7-[1-25]A-[1-40]A1'\]&include-descendants=true" \
		--parallel --parallel-max $threads --parallel-immediate
done

Note the above curl command performs 1000 requests. It is based on globbing in the URL - curl allows ranges such as [1-25]  in the URL, for example:

  http://example.com/archive[1996-1999]/vol[1-4].html

which would expand into a series of 16 requests to:

• http://example.com/archive1996/vol1.html
• http://example.com/archive1996/vol2.html
• ...
• http://example.com/archive1999/vol4.html

Results

Graphs

Image Added

Observations

• There were no failures during the tests (e.g. timeouts or refused connections).
• Performance increases nearly linearly with increasing thread count, up to the number of CPU cores.
• Performance stops increasing when the number of threads equals the number of CPU cores (expected).
• Verbose statistics show that each individual request takes around 0.14 seconds, regardless of thread count (but with multiple CPU cores, requests are really done in parallel).

Data sheets

Test scripts overview 

- performanceTest.sh
   Get 1000 times single large object from thousands of devices (1000, 2000, ..., 10000) and create metric after each run
- performanceRootTest.sh
   Get 10 times the whole data tree as one object from thousands of devices (1000, 2000, ..., 10000) and create metric after each run
- parallelGetRequestTest.sh
   Get one devices parallel from a database with 10000 devices, executed 10 times sequential

- buildup.sh
   Create the dataspace, create the schemaset, create the anchor and create the root node
- owb-msa221.zip
   The schemaset for the tests
- outNode.json
   The input for the root node creation
- createThousandNode.sh
   Helper script for the database creation
- innerNode.json
   The input for the sub node creation
- createMetric.sh
   Helper script for metric creation