CircuitPython - a Python implementation for teaching coding with microcontrollers https://git.suspectdevices.com/suspect-devices/circuitpython/atom?h=3.0.3 2018-01-24T18:33:46+00:00 2018-01-24T18:33:46+00:00 Scott Shawcroft scott.shawcroft@gmail.com 2018-01-24T00:22:05+00:00 urn:sha1:416abe33ed44e44d8f75342731080217e123278b This adapts the allocation process to start from either end of the heap when searching for free space. The default behavior is identical to the existing behavior where it starts with the lowest block and looks higher. Now it can also look from the highest block and lower depending on the long_lived parameter to gc_alloc. As the heap fills, the two sections may overlap. When they overlap, a collect may be triggered in order to keep the long lived section compact. However, free space is always eligable for each type of allocation. By starting from either of the end of the heap we have ability to separate short lived objects from long lived ones. This separation reduces heap fragmentation because long lived objects are easy to densely pack. Most objects are short lived initially but may be made long lived when they are referenced by a type or module. This involves copying the memory and then letting the collect phase free the old portion. QSTR pools and chunks are always long lived because they are never freed. The reallocation, collection and free processes are largely unchanged. They simply also maintain an index to the highest free block as well as the lowest. These indices are used to speed up the allocation search until the next collect. In practice, this change may slightly slow down import statements with the benefit that memory is much less fragmented afterwards. For example, a test import into a 20k heap that leaves ~6k free previously had the largest continuous free space of ~400 bytes. After this change, the largest continuous free space is over 3400 bytes. 2017-08-31T07:00:14+00:00 Damien George damien.p.george@gmail.com 2017-08-31T07:00:14+00:00 urn:sha1:ca21aed0a11903db04fc96056f8a08e452aaf504 2017-08-15T01:53:36+00:00 Stefan Naumann me@stefannaumann.de 2017-07-24T16:55:14+00:00 urn:sha1:ace9fb54053c29574bdf81ffacc5ddcf9d4b45d9 It enables all the DEBUG_printf outputs in the py/ source code. 2017-07-31T08:35:40+00:00 Alexander Steffen devel.20.webmeister@spamgourmet.com 2017-06-30T07:22:17+00:00 urn:sha1:55f33240f3d7051d4213629e92437a36f1fac50e There were several different spellings of MicroPython present in comments, when there should be only one. 2016-08-26T05:35:26+00:00 Damien George damien.p.george@gmail.com 2016-08-26T05:35:26+00:00 urn:sha1:5ffe1d8dc07930818bbac6a88bec2aa5bd973402 There can be stray pointers in memory blocks that are not properly zero'd after allocation. This patch adds a new config option to always zero all allocated memory (via gc_alloc and gc_realloc) and hence help to eliminate stray pointers. See issue #2195. 2016-02-23T13:53:38+00:00 Damien George damien.p.george@gmail.com 2016-02-23T13:53:38+00:00 urn:sha1:e9d1a94bf099d585d0f8d3b0dddb8e0a397afcff 2015-07-14T21:56:32+00:00 Damien George damien.p.george@gmail.com 2015-06-13T20:53:22+00:00 urn:sha1:ade9a052365247be5ed4ce8b53c2164a576a4a05 Previous to this patch all interned strings lived in their own malloc'd chunk. On average this wastes N/2 bytes per interned string, where N is the number-of-bytes for a quanta of the memory allocator (16 bytes on 32 bit archs). With this patch interned strings are concatenated into the same malloc'd chunk when possible. Such chunks are enlarged inplace when possible, and shrunk to fit when a new chunk is needed. RAM savings with this patch are highly varied, but should always show an improvement (unless only 3 or 4 strings are interned). New version typically uses about 70% of previous memory for the qstr data, and can lead to savings of around 10% of total memory footprint of a running script. Costs about 120 bytes code size on Thumb2 archs (depends on how many calls to gc_realloc are made). 2015-03-03T21:23:13+00:00 Damien George damien.p.george@gmail.com 2015-02-27T09:54:12+00:00 urn:sha1:d891452a73165966497f1c79b64276faaa664597 2015-01-07T20:33:00+00:00 Damien George damien.p.george@gmail.com 2015-01-01T23:30:53+00:00 urn:sha1:b4b10fd350852e321624d74983cca286091b55a1 This patch consolidates all global variables in py/ core into one place, in a global structure. Root pointers are all located together to make GC tracing easier and more efficient. 2015-01-01T20:32:09+00:00 Damien George damien.p.george@gmail.com 2015-01-01T20:27:54+00:00 urn:sha1:51dfcb4bb7613ed164952712d9a5235a7b833cde Addresses issue #1022.