diff options
Diffstat (limited to 'Modules')
| -rw-r--r-- | Modules/_collectionsmodule.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c index ca63f71..8b01a7f 100644 --- a/Modules/_collectionsmodule.c +++ b/Modules/_collectionsmodule.c @@ -118,9 +118,23 @@ static PyTypeObject deque_type; #define CHECK_NOT_END(link) #endif +/* A simple freelisting scheme is used to minimize calls to the memory + allocator. It accommodates common use cases where new blocks are being + added at about the same rate as old blocks are being freed. + */ + +#define MAXFREEBLOCKS 16 +static Py_ssize_t numfreeblocks = 0; +static block *freeblocks[MAXFREEBLOCKS]; + static block * newblock(void) { - block *b = PyMem_Malloc(sizeof(block)); + block *b; + if (numfreeblocks) { + numfreeblocks--; + return freeblocks[numfreeblocks]; + } + b = PyMem_Malloc(sizeof(block)); if (b != NULL) { return b; } @@ -131,7 +145,12 @@ newblock(void) { static void freeblock(block *b) { - PyMem_Free(b); + if (numfreeblocks < MAXFREEBLOCKS) { + freeblocks[numfreeblocks] = b; + numfreeblocks++; + } else { + PyMem_Free(b); + } } static PyObject * |