From 431d51de4c7219aa49e12f5468add009a517949b Mon Sep 17 00:00:00 2001 From: Dustin Howett Date: Tue, 21 Sep 2021 20:49:55 +0000 Subject: [PATCH] Merged PR 6286783: Release unneeded memory more eagerly from conhost This is equivalent to commit 8779249b1, but reflected from the OS repository. Retrieved from https://microsoft.visualstudio.com os.2020 OS official/rs_wdx_dxp_windev a4d67e9b05039f365a1a0c58e9c63474c58073a1 Related work items: MSFT-34777060 --- src/inc/til/u8u16convert.h | 8 ++++++++ src/server/ApiMessage.cpp | 18 ++++++++++++++++-- 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/src/inc/til/u8u16convert.h b/src/inc/til/u8u16convert.h index b4d3cd9f8..af6e4f9b7 100644 --- a/src/inc/til/u8u16convert.h +++ b/src/inc/til/u8u16convert.h @@ -55,6 +55,14 @@ namespace til // Terminal Implementation Library. Also: "Today I Learned" RETURN_HR_IF(E_ABORT, !base::CheckAdd(in.length(), _partialsLen).AssignIfValid(&capacity)); _buffer.clear(); + + // If we were previously called with a huge buffer we have an equally large _buffer. + // We shouldn't just keep this huge buffer around, if no one needs it anymore. + if (_buffer.capacity() > 16 * 1024 && (_buffer.capacity() >> 1) > capacity) + { + _buffer.shrink_to_fit(); + } + _buffer.reserve(capacity); // copy UTF-8 code units that were remaining from the previous call (if any) diff --git a/src/server/ApiMessage.cpp b/src/server/ApiMessage.cpp index 598111c88..9287965d3 100644 --- a/src/server/ApiMessage.cpp +++ b/src/server/ApiMessage.cpp @@ -104,7 +104,14 @@ try { RETURN_HR_IF(E_FAIL, State.ReadOffset > Descriptor.InputSize); - ULONG const cbReadSize = Descriptor.InputSize - State.ReadOffset; + const ULONG cbReadSize = Descriptor.InputSize - State.ReadOffset; + + // If we were previously called with a huge buffer we have an equally large _inputBuffer. + // We shouldn't just keep this huge buffer around, if no one needs it anymore. + if (_inputBuffer.capacity() > 16 * 1024 && (_inputBuffer.capacity() >> 1) > cbReadSize) + { + _inputBuffer.shrink_to_fit(); + } _inputBuffer.resize(cbReadSize); @@ -145,10 +152,17 @@ try ULONG cbWriteSize = Descriptor.OutputSize - State.WriteOffset; RETURN_IF_FAILED(ULongMult(cbWriteSize, cbFactor, &cbWriteSize)); + // If we were previously called with a huge buffer we have an equally large _outputBuffer. + // We shouldn't just keep this huge buffer around, if no one needs it anymore. + if (_outputBuffer.capacity() > 16 * 1024 && (_outputBuffer.capacity() >> 1) > cbWriteSize) + { + _outputBuffer.shrink_to_fit(); + } + _outputBuffer.resize(cbWriteSize); // 0 it out. - std::fill(_outputBuffer.begin(), _outputBuffer.end(), (BYTE)0); + std::fill_n(_outputBuffer.data(), _outputBuffer.size(), BYTE(0)); State.OutputBuffer = _outputBuffer.data(); State.OutputBufferSize = cbWriteSize;