BackgroundOps optimisation

Preallocated, non-pointer promises.

3 files changed, 33 insertions, 32 deletions

diff --git a/netfs/fuse/fuseFiles.cpp b/netfs/fuse/fuseFiles.cpp
index c5f2314..f47138d 100644
--- a/netfs/fuse/fuseFiles.cpp
+++ b/netfs/fuse/fuseFiles.cpp
@@ -171,51 +171,44 @@ namespace NetFS {
 			if (blockSizes.size1) {
 				callback(blockSizes.size1);
 			}
-			while (blockSizes.count--) {
+			while (blockSizes.countN--) {
 				callback(blockSizes.sizeN);
 			}
 		}
-
-		template<typename T>
-		auto
-		appendNewDefault(std::vector<std::unique_ptr<T>> & container)
-		{
-			return container.emplace_back(std::make_unique<T>()).get();
-		}
 	}
 
 	int
 	FuseApp::read(const char *, char * buf, size_t size, off_t offset, struct fuse_file_info * fileInfo)
 	{
 		try {
-			using BackgroundOps = std::vector<std::unique_ptr<std::promise<int>>>;
+			using BackgroundOps = std::vector<std::promise<int>>;
 			auto cpy = [buf](off_t blockOffset, const auto && data) -> int {
 				std::copy(data.begin(), data.end(), buf + blockOffset);
 				return safe {data.size()};
 			};
 			auto collateTotal = [](auto && ops) {
 				return std::accumulate(ops.begin(), ops.end(), 0, [](auto && total, auto & operation) {
-					return total += operation->get_future().get();
+					return total += operation.get_future().get();
 				});
 			};
 			auto openFile = getProxy<OpenFilePtr>(fileInfo->fh);
 			auto remote = openFile->remote;
 			auto blockSizes = openFile->blockSizes(size);
 			if (fcr->Async) {
-				BackgroundOps ops;
+				BackgroundOps ops(blockSizes.count());
 				blockSizeIterate(blockSizes,
-						[&ops, &offset, &openFile, &remote, blockOffset = 0U, &cpy](safe<size_t> blockSize) mutable {
-							const auto p = appendNewDefault(ops);
+						[&offset, &openFile, &remote, blockOffset = 0U, &cpy, opIter = ops.begin()](
+								safe<size_t> blockSize) mutable {
 							waitOnWriteRangeAndThen(blockSize, offset, openFile,
-									[p, offset, blockOffset, blockSize, &remote, &cpy](const auto &) {
+									[thisOp = opIter++, offset, blockOffset, blockSize, &remote, &cpy](const auto &) {
 										return remote->readAsync(
 												offset, blockSize,
-												[cpy, p, blockOffset](auto && resultBuf) {
-													p->set_value(
+												[cpy, thisOp, blockOffset](auto && resultBuf) {
+													thisOp->set_value(
 															cpy(blockOffset, std::forward<Ice::ByteSeq>(resultBuf)));
 												},
-												[p](auto error) {
-													p->set_exception(std::move(error));
+												[thisOp](auto error) {
+													thisOp->set_exception(std::move(error));
 												});
 									});
 							offset += blockSize;
@@ -224,17 +217,18 @@ namespace NetFS {
 				return collateTotal(ops);
 			}
 			if (openFile->bodyMaxSize < size) {
-				BackgroundOps ops;
-				blockSizeIterate(
-						blockSizes, [&offset, &remote, blockOffset = 0U, &ops, &cpy](safe<size_t> blockSize) mutable {
-							const auto p = appendNewDefault(ops);
+				BackgroundOps ops(blockSizes.count());
+				blockSizeIterate(blockSizes,
+						[&offset, &remote, blockOffset = 0U, &cpy, opIter = ops.begin()](
+								safe<size_t> blockSize) mutable {
+							auto thisOp = opIter++;
 							remote->readAsync(
 									offset, blockSize,
-									[cpy, p, blockOffset](auto && resultBuf) {
-										p->set_value(cpy(blockOffset, std::forward<Ice::ByteSeq>(resultBuf)));
+									[cpy, thisOp, blockOffset](auto && resultBuf) {
+										thisOp->set_value(cpy(blockOffset, std::forward<Ice::ByteSeq>(resultBuf)));
 									},
-									[p](auto error) {
-										p->set_exception(std::move(error));
+									[thisOp](auto error) {
+										thisOp->set_exception(std::move(error));
 									});
 							offset += blockSize;
 							blockOffset += blockSize;
@@ -301,23 +295,29 @@ namespace NetFS {
 	FuseApp::OpenFile::blockSizes(size_t total, size_t max) noexcept
 	{
 		if (max >= total) { // Simple case, all in remainder block
-			return {.size1 = total, .sizeN = 0, .count = 0};
+			return {.size1 = total, .sizeN = 0, .countN = 0};
 		}
 		if (total % max == 0) { // Simplish case, multiples of max
-			return {.size1 = 0, .sizeN = max, .count = total / max};
+			return {.size1 = 0, .sizeN = max, .countN = total / max};
 		}
 		const auto blocks = (total / max);
 		const auto blockSize = (total / (blocks + 1)) + 1;
 		const auto batchTotal = blockSize * blocks;
 		const auto remainder = total - batchTotal;
 
-		return {.size1 = remainder, .sizeN = blockSize, .count = blocks};
+		return {.size1 = remainder, .sizeN = blockSize, .countN = blocks};
 	}
 
 	size_t
 	FuseApp::OpenFile::BlockSizes::total() const noexcept
 	{
-		return size1 + (sizeN * count);
+		return size1 + (sizeN * countN);
+	}
+
+	size_t
+	FuseApp::OpenFile::BlockSizes::count() const noexcept
+	{
+		return countN + (size1 ? 1 : 0);
 	}
 
 	ssize_t
diff --git a/netfs/fuse/fuseFiles.h b/netfs/fuse/fuseFiles.h
index 4fe38e5..9742236 100644
--- a/netfs/fuse/fuseFiles.h
+++ b/netfs/fuse/fuseFiles.h
@@ -12,9 +12,10 @@ namespace NetFS {
 		void wait() const;
 
 		struct BlockSizes {
-			size_t size1, sizeN, count;
+			size_t size1, sizeN, countN;
 			auto operator<=>(const BlockSizes &) const = default;
 			[[nodiscard]] size_t total() const noexcept;
+			[[nodiscard]] size_t count() const noexcept;
 		};
 
 		[[nodiscard]] static BlockSizes blockSizes(size_t total, size_t max) noexcept;
diff --git a/netfs/unittests/testEdgeCases.cpp b/netfs/unittests/testEdgeCases.cpp
index 75ff3aa..07f2c18 100644
--- a/netfs/unittests/testEdgeCases.cpp
+++ b/netfs/unittests/testEdgeCases.cpp
@@ -131,7 +131,7 @@ namespace std {
 	ostream &
 	operator<<(ostream & s, const FuseMock::OpenFile::BlockSizes & b)
 	{
-		return s << '(' << b.size1 << '+' << b.sizeN << '*' << b.count << ')';
+		return s << '(' << b.size1 << '+' << b.sizeN << '*' << b.countN << ')';
 	}
 }