From d5aec7ba48c395db3386172b892e334bc55e44d3 Mon Sep 17 00:00:00 2001 From: Antoine Pitrou Date: Mon, 13 Apr 2015 20:53:43 +0200 Subject: Issue #21116: Avoid blowing memory when allocating a multiprocessing shared array that's larger than 50% of the available RAM. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch by Médéric Boquien. --- Lib/multiprocessing/heap.py | 9 ++++++++- Misc/ACKS | 1 + Misc/NEWS | 3 +++ 3 files changed, 12 insertions(+), 1 deletion(-) diff --git a/Lib/multiprocessing/heap.py b/Lib/multiprocessing/heap.py index 333b3ba..44d9638 100644 --- a/Lib/multiprocessing/heap.py +++ b/Lib/multiprocessing/heap.py @@ -71,7 +71,14 @@ else: os.unlink(name) util.Finalize(self, os.close, (self.fd,)) with open(self.fd, 'wb', closefd=False) as f: - f.write(b'\0'*size) + bs = 1024 * 1024 + if size >= bs: + zeros = b'\0' * bs + for _ in range(size // bs): + f.write(zeros) + del zeros + f.write(b'\0' * (size % bs)) + assert f.tell() == size self.buffer = mmap.mmap(self.fd, self.size) def reduce_arena(a): diff --git a/Misc/ACKS b/Misc/ACKS index 9a3de4e..d1074bd 100644 --- a/Misc/ACKS +++ b/Misc/ACKS @@ -154,6 +154,7 @@ Wouter Bolsterlee Gawain Bolton Forest Bond Gregory Bond +Médéric Boquien Matias Bordese Jonas Borgström Jurjen Bos diff --git a/Misc/NEWS b/Misc/NEWS index 78db876..e4574a1 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -29,6 +29,9 @@ Core and Builtins Library ------- +- Issue #21116: Avoid blowing memory when allocating a multiprocessing shared + array that's larger than 50% of the available RAM. Patch by Médéric Boquien. + - Issue #22982: Improve BOM handling when seeking to multiple positions of a writable text file. -- cgit v0.12