Cuni: PyPy for low-latency systems

Antonio Cuni writes
about recent work to support running Python code with low latency
requirements under PyPy. 'As we said, the total cost of memory
management is less on PyPy than on CPython, and it's one of the reasons why
PyPy is so fast. However, one big disadvantage is that while on CPython the
cost of memory management is spread all over the execution of the program,
on PyPy it is concentrated into GC runs, causing observable pauses which
interrupt the execution of the user program. To avoid excessively long
pauses, the PyPy GC has been using an incremental strategy since 2013. The
GC runs as a series of 'steps', letting the user program to progress
between each step.'