From 41c7e96f1a81ea416ebb3ba45f2815e0202d6b75 Mon Sep 17 00:00:00 2001 From: Bert Belder Date: Sun, 28 Apr 2019 21:31:10 +0200 Subject: Refactor zero-copy buffers for performance and to prevent memory leaks * In order to prevent ArrayBuffers from getting garbage collected by V8, we used to store a v8::Persistent in a map. This patch introduces a custom ArrayBuffer allocator which doesn't use Persistent handles, but instead stores a pointer to the actual ArrayBuffer data alongside with a reference count. Since creating Persistent handles has quite a bit of overhead, this change significantly increases performance. Various HTTP server benchmarks report about 5-10% more requests per second than before. * Previously the Persistent handle that prevented garbage collection had to be released manually, and this wasn't always done, which was causing memory leaks. This has been resolved by introducing a new `PinnedBuf` type in both Rust and C++ that automatically re-enables garbage collection when it goes out of scope. * Zero-copy buffers are now correctly wrapped in an Option if there is a possibility that they're not present. This clears up a correctness issue where we were creating zero-length slices from a null pointer, which is against the rules. --- core/libdeno/test.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'core/libdeno/test.h') diff --git a/core/libdeno/test.h b/core/libdeno/test.h index dd5dc99b2..d7e6a3f80 100644 --- a/core/libdeno/test.h +++ b/core/libdeno/test.h @@ -6,7 +6,7 @@ #include "testing/gtest/include/gtest/gtest.h" extern deno_snapshot snapshot; // Loaded in libdeno/test.cc -const deno_buf empty = {nullptr, 0, nullptr, 0, 0}; +const deno_buf empty = {nullptr, 0, nullptr, 0}; const deno_snapshot empty_snapshot = {nullptr, 0}; #endif // TEST_H_ -- cgit v1.2.3