misc_aes.py and misc_mandel.py are adapted from sources in this repository.
misc_pystone.py is the standard Python pystone test. misc_raytrace.py is
written from scratch.
This benchmarking test suite is intended to be run on any MicroPython
target. As such all tests are parameterised with N and M: N is the
approximate CPU frequency (in MHz) of the target and M is the approximate
amount of heap memory (in kbytes) available on the target. When running
the benchmark suite these parameters must be specified and then each test
is tuned to run on that target in a reasonable time (<1 second).
The test scripts are not standalone: they require adding some extra code at
the end to run the test with the appropriate parameters. This is done
automatically by the run-perfbench.py script, in such a way that imports
are minimised (so the tests can be run on targets without filesystem
support).
To interface with the benchmarking framework, each test provides a
bm_params dict and a bm_setup function, with the later taking a set of
parameters (chosen based on N, M) and returning a pair of functions, one to
run the test and one to get the results.
When running the test the number of microseconds taken by the test are
recorded. Then this is converted into a benchmark score by inverting it
(so higher number is faster) and normalising it with an appropriate factor
(based roughly on the amount of work done by the test, eg number of
iterations).
Test outputs are also compared against a "truth" value, computed by running
the test with CPython. This provides a basic way of making sure the test
actually ran correctly.
Each test is run multiple times and the results averaged and standard
deviation computed. This is output as a summary of the test.
To make comparisons of performance across different runs the
run-perfbench.py script also includes a diff mode that reads in the output
of two previous runs and computes the difference in performance. Reports
are given as a percentage change in performance with a combined standard
deviation to give an indication if the noise in the benchmarking is less
than the thing that is being measured.
Example invocations for PC, pyboard and esp8266 targets respectively:
$ ./run-perfbench.py 1000 1000
$ ./run-perfbench.py --pyboard 100 100
$ ./run-perfbench.py --pyboard --device /dev/ttyUSB0 50 25
Reuse the implementation for bytes since it works the same way regardless
of the underlying type. This method gets added for CPython compatibility
of bytearray, but to keep the code simple and small array.array now also
has a working decode method, which is non-standard but doesn't hurt.
This allows figuring out the number of bytes in the memoryview object as
len(memview) * memview.itemsize.
The feature is enabled via MICROPY_PY_BUILTINS_MEMORYVIEW_ITEMSIZE and is
disabled by default.
It consists of:
1. "do_handhake" param (default True) to wrap_socket(). If it's False,
handshake won't be performed by wrap_socket(), as it would be done in
blocking way normally. Instead, SSL socket can be set to non-blocking mode,
and handshake would be performed before the first read/write request (by
just returning EAGAIN to these requests, while instead reading/writing/
processing handshake over the connection). Unfortunately, axTLS doesn't
really support non-blocking handshake correctly. So, while framework for
this is implemented on MicroPython's module side, in case of axTLS, it
won't work reliably.
2. Implementation of .setblocking() method. It must be called on SSL socket
for blocking vs non-blocking operation to be handled correctly (for
example, it's not enough to wrap non-blocking socket with wrap_socket()
call - resulting SSL socket won't be itself non-blocking). Note that
.setblocking() propagates call to the underlying socket object, as
expected.
When running Linux on WSL, Popen.kill() can raise a ProcessLookupError if
the process does not exist anymore, which can happen here since the
previous statement already tries to close the process by sending Ctrl-D to
the running repl. This doesn't seem to be a problem on other OSes, so just
swallow the exception silently since it indicates the process has been
closed already, which after all is what we want.
This is an implementation of a sliding qstr window used to reduce the
number of qstrs stored in a .mpy file. The window size is configured to 32
entries which takes a fixed 64 bytes (16-bits each) on the C stack when
loading/saving a .mpy file. It allows to remember the most recent 32 qstrs
so they don't need to be stored again in the .mpy file. The qstr window
uses a simple least-recently-used mechanism to discard the least recently
used qstr when the window overflows (similar to dictionary compression).
This scheme only needs a single pass to save/load the .mpy file.
Reduces mpy file size by about 25% with a window size of 32.