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+scripts for automated testing of zstd
+================================
+
+#### test-zstd-versions.py - script for testing zstd interoperability between versions
+
+This script creates `versionsTest` directory to which zstd repository is cloned.
+Then all taged (released) versions of zstd are compiled.
+In the following step interoperability between zstd versions is checked.
+
+
+#### test-zstd-speed.py - script for testing zstd speed difference between commits
+
+This script creates `speedTest` directory to which zstd repository is cloned.
+Then it compiles all branches of zstd and performs a speed benchmark for a given list of files (the `testFileNames` parameter).
+After `sleepTime` (an optional parameter, default 300 seconds) seconds the script checks repository for new commits.
+If a new commit is found it's compiled and a speed benchmark for this commit is performed.
+The results of the speed benchmark are compared to the previous results.
+If compression or decompression speed for one of zstd levels is lower than `lowerLimit` (an optional parameter, default 0.98) the speed benchmark is restarted.
+If second results are lower than `lowerLimit` the warning e-mail is send to recipients from the list (the `emails` parameter).
+The speed benchmark is not performed if computers' load average is higher than `maxLoadAvg` (an optional parameter, default 0.75).
+
+The example usage:
+```./test-zstd-speed.py "silesia.tar calgary.tar" "email@gmail.com" --message "tested on my laptop" --sleepTime 60``` 
+
+The full list of parameters:
+```
+positional arguments:
+  testFileNames         file names list for speed benchmark
+  emails                list of e-mail addresses to send warnings
+
+optional arguments:
+  -h, --help            show this help message and exit
+  --message MESSAGE     attach an additional message to e-mail
+  --lowerLimit LOWERLIMIT
+                        send email if speed is lower than given limit
+  --maxLoadAvg MAXLOADAVG
+                        maximum load average to start testing
+  --lastCLevel LASTCLEVEL
+                        last compression level for testing
+  --sleepTime SLEEPTIME
+                        frequency of repository checking in seconds
+```