[llvm-branch-commits] [clang-tools-extra-branch] r368569 - Merging r368498:
Hans Wennborg via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Mon Aug 12 06:40:27 PDT 2019
Author: hans
Date: Mon Aug 12 06:40:27 2019
New Revision: 368569
URL: http://llvm.org/viewvc/llvm-project?rev=368569&view=rev
Log:
Merging r368498:
------------------------------------------------------------------------
r368498 | sammccall | 2019-08-10 01:03:32 +0200 (Sat, 10 Aug 2019) | 25 lines
clangd: use -j for background index pool
Summary:
clangd supports a -j option to limit the amount of threads to use for parsing
TUs. However, when using -background-index (the default in later versions of
clangd), the parallelism used by clangd defaults to the hardware_parallelisn,
i.e. number of physical cores.
On shared hardware environments, with large projects, this can significantly
affect performance with no way to tune it down.
This change makes the -j parameter apply equally to parsing and background
index. It's not perfect, because the total number of threads is 2x the -j value,
which may still be unexpected. But at least this change allows users to prevent
clangd using all CPU cores.
Reviewers: kadircet, sammccall
Reviewed By: sammccall
Subscribers: javed.absar, jfb, sammccall, ilya-biryukov, MaskRay, jkorous, arphaman, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D66031
------------------------------------------------------------------------
Modified:
clang-tools-extra/branches/release_90/ (props changed)
clang-tools-extra/branches/release_90/clangd/ClangdServer.cpp
clang-tools-extra/branches/release_90/clangd/TUScheduler.cpp
clang-tools-extra/branches/release_90/clangd/tool/ClangdMain.cpp
Propchange: clang-tools-extra/branches/release_90/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Mon Aug 12 06:40:27 2019
@@ -1 +1 @@
-/clang-tools-extra/trunk:366443,366451,366455,366545,366559,366687,366811,366880,366900,366991-366992,367112,367687,368019,368058
+/clang-tools-extra/trunk:366443,366451,366455,366545,366559,366687,366811,366880,366900,366991-366992,367112,367687,368019,368058,368498
Modified: clang-tools-extra/branches/release_90/clangd/ClangdServer.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/branches/release_90/clangd/ClangdServer.cpp?rev=368569&r1=368568&r2=368569&view=diff
==============================================================================
--- clang-tools-extra/branches/release_90/clangd/ClangdServer.cpp (original)
+++ clang-tools-extra/branches/release_90/clangd/ClangdServer.cpp Mon Aug 12 06:40:27 2019
@@ -38,9 +38,11 @@
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
#include <future>
#include <memory>
#include <mutex>
+#include <type_traits>
namespace clang {
namespace clangd {
@@ -101,8 +103,7 @@ ClangdServer::ClangdServer(const GlobalC
: nullptr),
GetClangTidyOptions(Opts.GetClangTidyOptions),
SuggestMissingIncludes(Opts.SuggestMissingIncludes),
- TweakFilter(Opts.TweakFilter),
- WorkspaceRoot(Opts.WorkspaceRoot),
+ TweakFilter(Opts.TweakFilter), WorkspaceRoot(Opts.WorkspaceRoot),
// Pass a callback into `WorkScheduler` to extract symbols from a newly
// parsed file and rebuild the file index synchronously each time an AST
// is parsed.
@@ -128,7 +129,8 @@ ClangdServer::ClangdServer(const GlobalC
BackgroundIdx = llvm::make_unique<BackgroundIndex>(
Context::current().clone(), FSProvider, CDB,
BackgroundIndexStorage::createDiskBackedStorageFactory(
- [&CDB](llvm::StringRef File) { return CDB.getProjectInfo(File); }));
+ [&CDB](llvm::StringRef File) { return CDB.getProjectInfo(File); }),
+ std::max(Opts.AsyncThreadsCount, 1u));
AddIndex(BackgroundIdx.get());
}
if (DynamicIdx)
Modified: clang-tools-extra/branches/release_90/clangd/TUScheduler.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/branches/release_90/clangd/TUScheduler.cpp?rev=368569&r1=368568&r2=368569&view=diff
==============================================================================
--- clang-tools-extra/branches/release_90/clangd/TUScheduler.cpp (original)
+++ clang-tools-extra/branches/release_90/clangd/TUScheduler.cpp Mon Aug 12 06:40:27 2019
@@ -54,6 +54,7 @@
#include "llvm/ADT/ScopeExit.h"
#include "llvm/Support/Errc.h"
#include "llvm/Support/Path.h"
+#include "llvm/Support/Threading.h"
#include <algorithm>
#include <memory>
#include <queue>
@@ -799,10 +800,10 @@ std::string renderTUAction(const TUActio
} // namespace
unsigned getDefaultAsyncThreadsCount() {
- unsigned HardwareConcurrency = std::thread::hardware_concurrency();
- // C++ standard says that hardware_concurrency()
- // may return 0, fallback to 1 worker thread in
- // that case.
+ unsigned HardwareConcurrency = llvm::heavyweight_hardware_concurrency();
+ // heavyweight_hardware_concurrency may fall back to hardware_concurrency.
+ // C++ standard says that hardware_concurrency() may return 0; fallback to 1
+ // worker thread in that case.
if (HardwareConcurrency == 0)
return 1;
return HardwareConcurrency;
Modified: clang-tools-extra/branches/release_90/clangd/tool/ClangdMain.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/branches/release_90/clangd/tool/ClangdMain.cpp?rev=368569&r1=368568&r2=368569&view=diff
==============================================================================
--- clang-tools-extra/branches/release_90/clangd/tool/ClangdMain.cpp (original)
+++ clang-tools-extra/branches/release_90/clangd/tool/ClangdMain.cpp Mon Aug 12 06:40:27 2019
@@ -267,7 +267,8 @@ list<std::string> TweakList{
opt<unsigned> WorkerThreadsCount{
"j",
cat(Misc),
- desc("Number of async workers used by clangd"),
+ desc("Number of async workers used by clangd. Background index also "
+ "uses this many workers."),
init(getDefaultAsyncThreadsCount()),
};
@@ -308,7 +309,8 @@ opt<PCHStorageFlag> PCHStorage{
opt<bool> Sync{
"sync",
cat(Misc),
- desc("Parse on main thread. If set, -j is ignored"),
+ desc("Handle client requests on main thread. Background index still uses "
+ "its own thread."),
init(false),
Hidden,
};
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