Merge changes from topic "ota-tune-1" into main
* changes:
Allow direct reads on source device
libsnapshot: Tune readahead during OTA for source and COW block device
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index 08a79ba..d102863 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -826,6 +826,9 @@
bool DeleteDeviceIfExists(const std::string& name,
const std::chrono::milliseconds& timeout_ms = {});
+ // Set read-ahead size during OTA
+ void SetReadAheadSize(const std::string& entry_block_device, off64_t size_kb);
+
android::dm::IDeviceMapper& dm_;
std::unique_ptr<IDeviceInfo> device_;
std::string metadata_dir_;
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index 79cebab..f6a35a8 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -30,6 +30,7 @@
#include <android-base/logging.h>
#include <android-base/parseint.h>
#include <android-base/properties.h>
+#include <android-base/stringprintf.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include <cutils/sockets.h>
@@ -82,12 +83,28 @@
using std::chrono::duration_cast;
using namespace std::chrono_literals;
using namespace std::string_literals;
+using android::base::Realpath;
+using android::base::StringPrintf;
static constexpr char kBootSnapshotsWithoutSlotSwitch[] =
"/metadata/ota/snapshot-boot-without-slot-switch";
static constexpr char kBootIndicatorPath[] = "/metadata/ota/snapshot-boot";
static constexpr char kRollbackIndicatorPath[] = "/metadata/ota/rollback-indicator";
static constexpr auto kUpdateStateCheckInterval = 2s;
+/*
+ * The readahead size is set to 32kb so that
+ * there is no significant memory pressure (/proc/pressure/memory) during boot.
+ * After OTA, during boot, partitions are scanned before marking slot as successful.
+ * This scan will trigger readahead both on source and COW block device thereby
+ * leading to Inactive(file) pages to be very high.
+ *
+ * A lower value may help reduce memory pressure further, however, that will
+ * increase the boot time. Thus, for device which don't care about OTA boot
+ * time, they could use O_DIRECT functionality wherein the I/O to the source
+ * block device will be O_DIRECT.
+ */
+static constexpr auto kCowReadAheadSizeKb = 32;
+static constexpr auto kSourceReadAheadSizeKb = 32;
// Note: IImageManager is an incomplete type in the header, so the default
// destructor doesn't work.
@@ -1748,6 +1765,9 @@
snapuserd_argv->emplace_back(std::move(message));
}
+ SetReadAheadSize(cow_image_device, kCowReadAheadSizeKb);
+ SetReadAheadSize(source_device, kSourceReadAheadSizeKb);
+
// Do not attempt to connect to the new snapuserd yet, it hasn't
// been started. We do however want to wait for the misc device
// to have been created.
@@ -4407,5 +4427,31 @@
return true;
}
+void SnapshotManager::SetReadAheadSize(const std::string& entry_block_device, off64_t size_kb) {
+ std::string block_device;
+ if (!Realpath(entry_block_device, &block_device)) {
+ PLOG(ERROR) << "Failed to realpath " << entry_block_device;
+ return;
+ }
+
+ static constexpr std::string_view kDevBlockPrefix("/dev/block/");
+ if (!android::base::StartsWith(block_device, kDevBlockPrefix)) {
+ LOG(ERROR) << block_device << " is not a block device";
+ return;
+ }
+
+ std::string block_name = block_device.substr(kDevBlockPrefix.length());
+ std::string sys_partition =
+ android::base::StringPrintf("/sys/class/block/%s/partition", block_name.c_str());
+ struct stat info;
+ if (lstat(sys_partition.c_str(), &info) == 0) {
+ block_name += "/..";
+ }
+ std::string sys_ra = android::base::StringPrintf("/sys/class/block/%s/queue/read_ahead_kb",
+ block_name.c_str());
+ std::string size = std::to_string(size_kb);
+ android::base::WriteStringToFile(size, sys_ra.c_str());
+}
+
} // namespace snapshot
} // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/extractor.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/extractor.cpp
index c5718d5..c85331b 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/extractor.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/extractor.cpp
@@ -41,7 +41,7 @@
bool Extractor::Init() {
auto opener = factory_.CreateTestOpener(control_name_);
handler_ = std::make_shared<SnapshotHandler>(control_name_, cow_path_, base_path_, base_path_,
- opener, 1, false, false);
+ opener, 1, false, false, false);
if (!handler_->InitCowDevice()) {
return false;
}
@@ -50,7 +50,7 @@
}
read_worker_ = std::make_unique<ReadWorker>(cow_path_, base_path_, control_name_, base_path_,
- handler_->GetSharedPtr(), opener);
+ handler_->GetSharedPtr(), opener, false);
if (!read_worker_->Init()) {
return false;
}
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.cpp
index ffd7a4b..711e704 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.cpp
@@ -51,10 +51,11 @@
std::shared_ptr<HandlerThread> SnapshotHandlerManager::AddHandler(
const std::string& misc_name, const std::string& cow_device_path,
const std::string& backing_device, const std::string& base_path_merge,
- std::shared_ptr<IBlockServerOpener> opener, int num_worker_threads, bool use_iouring) {
- auto snapuserd = std::make_shared<SnapshotHandler>(misc_name, cow_device_path, backing_device,
- base_path_merge, opener, num_worker_threads,
- use_iouring, perform_verification_);
+ std::shared_ptr<IBlockServerOpener> opener, int num_worker_threads, bool use_iouring,
+ bool o_direct) {
+ auto snapuserd = std::make_shared<SnapshotHandler>(
+ misc_name, cow_device_path, backing_device, base_path_merge, opener, num_worker_threads,
+ use_iouring, perform_verification_, o_direct);
if (!snapuserd->InitCowDevice()) {
LOG(ERROR) << "Failed to initialize Snapuserd";
return nullptr;
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.h b/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.h
index ff6ee8f..f23f07e 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.h
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.h
@@ -57,7 +57,8 @@
const std::string& backing_device,
const std::string& base_path_merge,
std::shared_ptr<IBlockServerOpener> opener,
- int num_worker_threads, bool use_iouring) = 0;
+ int num_worker_threads, bool use_iouring,
+ bool o_direct) = 0;
// Start serving requests on a snapshot handler.
virtual bool StartHandler(const std::string& misc_name) = 0;
@@ -96,7 +97,8 @@
const std::string& backing_device,
const std::string& base_path_merge,
std::shared_ptr<IBlockServerOpener> opener,
- int num_worker_threads, bool use_iouring) override;
+ int num_worker_threads, bool use_iouring,
+ bool o_direct) override;
bool StartHandler(const std::string& misc_name) override;
bool DeleteHandler(const std::string& misc_name) override;
bool InitiateMerge(const std::string& misc_name) override;
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/merge_worker.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/merge_worker.cpp
index 3a56669..bcf9aab 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/merge_worker.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/merge_worker.cpp
@@ -557,7 +557,7 @@
return true;
}
- if (!SetThreadPriority(kNiceValueForMergeThreads)) {
+ if (!SetThreadPriority(ANDROID_PRIORITY_BACKGROUND)) {
SNAP_PLOG(ERROR) << "Failed to set thread priority";
}
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.cpp
index 431baf0..f1d4065 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.cpp
@@ -31,16 +31,19 @@
void ReadWorker::CloseFds() {
block_server_ = {};
backing_store_fd_ = {};
+ backing_store_direct_fd_ = {};
Worker::CloseFds();
}
ReadWorker::ReadWorker(const std::string& cow_device, const std::string& backing_device,
const std::string& misc_name, const std::string& base_path_merge,
std::shared_ptr<SnapshotHandler> snapuserd,
- std::shared_ptr<IBlockServerOpener> opener)
+ std::shared_ptr<IBlockServerOpener> opener, bool direct_read)
: Worker(cow_device, misc_name, base_path_merge, snapuserd),
backing_store_device_(backing_device),
- block_server_opener_(opener) {}
+ direct_read_(direct_read),
+ block_server_opener_(opener),
+ aligned_buffer_(std::unique_ptr<void, decltype(&::free)>(nullptr, &::free)) {}
// Start the replace operation. This will read the
// internal COW format and if the block is compressed,
@@ -61,6 +64,17 @@
}
SNAP_LOG(DEBUG) << " ReadFromBaseDevice...: new-block: " << cow_op->new_block
<< " Op: " << *cow_op;
+
+ if (direct_read_ && IsBlockAligned(offset)) {
+ if (!android::base::ReadFullyAtOffset(backing_store_direct_fd_, aligned_buffer_.get(),
+ BLOCK_SZ, offset)) {
+ SNAP_PLOG(ERROR) << "O_DIRECT Read failed at offset: " << offset;
+ return false;
+ }
+ std::memcpy(buffer, aligned_buffer_.get(), BLOCK_SZ);
+ return true;
+ }
+
if (!android::base::ReadFullyAtOffset(backing_store_fd_, buffer, BLOCK_SZ, offset)) {
std::string op;
if (cow_op->type() == kCowCopyOp)
@@ -201,6 +215,24 @@
return false;
}
+ if (direct_read_) {
+ backing_store_direct_fd_.reset(open(backing_store_device_.c_str(), O_RDONLY | O_DIRECT));
+ if (backing_store_direct_fd_ < 0) {
+ SNAP_PLOG(ERROR) << "Open Failed with O_DIRECT: " << backing_store_direct_fd_;
+ direct_read_ = false;
+ } else {
+ void* aligned_addr;
+ ssize_t page_size = getpagesize();
+ if (posix_memalign(&aligned_addr, page_size, page_size) < 0) {
+ direct_read_ = false;
+ SNAP_PLOG(ERROR) << "posix_memalign failed "
+ << " page_size: " << page_size << " read_sz: " << page_size;
+ } else {
+ aligned_buffer_.reset(aligned_addr);
+ }
+ }
+ }
+
block_server_ = block_server_opener_->Open(this, PAYLOAD_BUFFER_SZ);
if (!block_server_) {
SNAP_PLOG(ERROR) << "Unable to open block server";
@@ -214,7 +246,7 @@
pthread_setname_np(pthread_self(), "ReadWorker");
- if (!SetThreadPriority(kNiceValueForMergeThreads)) {
+ if (!SetThreadPriority(ANDROID_PRIORITY_NORMAL)) {
SNAP_PLOG(ERROR) << "Failed to set thread priority";
}
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.h b/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.h
index 6dbae81..1aff50c 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.h
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.h
@@ -28,7 +28,7 @@
ReadWorker(const std::string& cow_device, const std::string& backing_device,
const std::string& misc_name, const std::string& base_path_merge,
std::shared_ptr<SnapshotHandler> snapuserd,
- std::shared_ptr<IBlockServerOpener> opener);
+ std::shared_ptr<IBlockServerOpener> opener, bool direct_read = false);
bool Run();
bool Init() override;
@@ -59,11 +59,14 @@
std::string backing_store_device_;
unique_fd backing_store_fd_;
+ unique_fd backing_store_direct_fd_;
+ bool direct_read_ = false;
std::shared_ptr<IBlockServerOpener> block_server_opener_;
std::unique_ptr<IBlockServer> block_server_;
std::basic_string<uint8_t> xor_buffer_;
+ std::unique_ptr<void, decltype(&::free)> aligned_buffer_;
};
} // namespace snapshot
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp
index 9b8c70d..05ba047 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp
@@ -36,7 +36,7 @@
SnapshotHandler::SnapshotHandler(std::string misc_name, std::string cow_device,
std::string backing_device, std::string base_path_merge,
std::shared_ptr<IBlockServerOpener> opener, int num_worker_threads,
- bool use_iouring, bool perform_verification) {
+ bool use_iouring, bool perform_verification, bool o_direct) {
misc_name_ = std::move(misc_name);
cow_device_ = std::move(cow_device);
backing_store_device_ = std::move(backing_device);
@@ -45,13 +45,14 @@
num_worker_threads_ = num_worker_threads;
is_io_uring_enabled_ = use_iouring;
perform_verification_ = perform_verification;
+ o_direct_ = o_direct;
}
bool SnapshotHandler::InitializeWorkers() {
for (int i = 0; i < num_worker_threads_; i++) {
auto wt = std::make_unique<ReadWorker>(cow_device_, backing_store_device_, misc_name_,
base_path_merge_, GetSharedPtr(),
- block_server_opener_);
+ block_server_opener_, o_direct_);
if (!wt->Init()) {
SNAP_LOG(ERROR) << "Thread initialization failed";
return false;
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h
index fa1e7a0..9b7238a 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h
@@ -47,6 +47,7 @@
#include <snapuserd/snapuserd_buffer.h>
#include <snapuserd/snapuserd_kernel.h>
#include <storage_literals/storage_literals.h>
+#include <system/thread_defs.h>
#include "snapuserd_readahead.h"
#include "snapuserd_verify.h"
@@ -62,8 +63,6 @@
static constexpr int kNumWorkerThreads = 4;
-static constexpr int kNiceValueForMergeThreads = -5;
-
#define SNAP_LOG(level) LOG(level) << misc_name_ << ": "
#define SNAP_PLOG(level) PLOG(level) << misc_name_ << ": "
@@ -105,7 +104,7 @@
public:
SnapshotHandler(std::string misc_name, std::string cow_device, std::string backing_device,
std::string base_path_merge, std::shared_ptr<IBlockServerOpener> opener,
- int num_workers, bool use_iouring, bool perform_verification);
+ int num_workers, bool use_iouring, bool perform_verification, bool o_direct);
bool InitCowDevice();
bool Start();
@@ -247,6 +246,7 @@
bool perform_verification_ = true;
bool resume_merge_ = false;
bool merge_complete_ = false;
+ bool o_direct_ = false;
std::unique_ptr<UpdateVerify> update_verify_;
std::shared_ptr<IBlockServerOpener> block_server_opener_;
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp
index 034cda1..c08c1b1 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp
@@ -778,7 +778,7 @@
InitializeIouring();
- if (!SetThreadPriority(kNiceValueForMergeThreads)) {
+ if (!SetThreadPriority(ANDROID_PRIORITY_BACKGROUND)) {
SNAP_PLOG(ERROR) << "Failed to set thread priority";
}
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp
index 6eee357..0b881b6 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp
@@ -346,7 +346,8 @@
std::shared_ptr<HandlerThread> UserSnapshotServer::AddHandler(const std::string& misc_name,
const std::string& cow_device_path,
const std::string& backing_device,
- const std::string& base_path_merge) {
+ const std::string& base_path_merge,
+ const bool o_direct) {
// We will need multiple worker threads only during
// device boot after OTA. For all other purposes,
// one thread is sufficient. We don't want to consume
@@ -368,7 +369,7 @@
auto opener = block_server_factory_->CreateOpener(misc_name);
return handlers_->AddHandler(misc_name, cow_device_path, backing_device, base_path_merge,
- opener, num_worker_threads, io_uring_enabled_);
+ opener, num_worker_threads, io_uring_enabled_, o_direct);
}
bool UserSnapshotServer::WaitForSocket() {
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.h b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.h
index 9926071..3013c47 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.h
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.h
@@ -86,7 +86,8 @@
std::shared_ptr<HandlerThread> AddHandler(const std::string& misc_name,
const std::string& cow_device_path,
const std::string& backing_device,
- const std::string& base_path_merge);
+ const std::string& base_path_merge,
+ bool o_direct = false);
bool StartHandler(const std::string& misc_name);
void SetTerminating() { terminating_ = true; }
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
index 73c3cbf..8ddb0f4 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
@@ -59,10 +59,16 @@
using testing::AssertionFailure;
using testing::AssertionResult;
using testing::AssertionSuccess;
+using ::testing::TestWithParam;
-class SnapuserdTestBase : public ::testing::TestWithParam<bool> {
+struct TestParam {
+ bool io_uring;
+ bool o_direct;
+};
+
+class SnapuserdTestBase : public ::testing::TestWithParam<TestParam> {
protected:
- void SetUp() override;
+ virtual void SetUp() override;
void TearDown() override;
void CreateBaseDevice();
void CreateCowDevice();
@@ -628,9 +634,10 @@
auto factory = harness_->GetBlockServerFactory();
auto opener = factory->CreateOpener(system_device_ctrl_name_);
handlers_->DisableVerification();
- auto handler =
- handlers_->AddHandler(system_device_ctrl_name_, cow_system_->path, base_dev_->GetPath(),
- base_dev_->GetPath(), opener, 1, GetParam());
+ const TestParam params = GetParam();
+ auto handler = handlers_->AddHandler(system_device_ctrl_name_, cow_system_->path,
+ base_dev_->GetPath(), base_dev_->GetPath(), opener, 1,
+ params.io_uring, params.o_direct);
ASSERT_NE(handler, nullptr);
ASSERT_NE(handler->snapuserd(), nullptr);
#ifdef __ANDROID__
@@ -898,9 +905,10 @@
opener_ = factory_.CreateTestOpener(system_device_ctrl_name_);
ASSERT_NE(opener_, nullptr);
+ const TestParam params = GetParam();
handler_ = std::make_shared<SnapshotHandler>(system_device_ctrl_name_, cow_system_->path,
base_dev_->GetPath(), base_dev_->GetPath(),
- opener_, 1, false, false);
+ opener_, 1, false, false, params.o_direct);
ASSERT_TRUE(handler_->InitCowDevice());
ASSERT_TRUE(handler_->InitializeWorkers());
@@ -990,14 +998,28 @@
return {false, true};
}
-std::string IoUringConfigName(const testing::TestParamInfo<SnapuserdTest::ParamType>& info) {
- return info.param ? "io_uring" : "sync";
+std::vector<TestParam> GetTestConfigs() {
+ std::vector<TestParam> testParams;
+ std::vector<bool> uring_configs = GetIoUringConfigs();
+
+ for (bool config : uring_configs) {
+ TestParam param;
+ param.io_uring = config;
+ param.o_direct = false;
+ testParams.push_back(std::move(param));
+ }
+
+ for (bool config : uring_configs) {
+ TestParam param;
+ param.io_uring = config;
+ param.o_direct = true;
+ testParams.push_back(std::move(param));
+ }
+ return testParams;
}
-INSTANTIATE_TEST_SUITE_P(Io, SnapuserdTest, ::testing::ValuesIn(GetIoUringConfigs()),
- IoUringConfigName);
-INSTANTIATE_TEST_SUITE_P(Io, HandlerTest, ::testing::ValuesIn(GetIoUringConfigs()),
- IoUringConfigName);
+INSTANTIATE_TEST_SUITE_P(Io, SnapuserdTest, ::testing::ValuesIn(GetTestConfigs()));
+INSTANTIATE_TEST_SUITE_P(Io, HandlerTest, ::testing::ValuesIn(GetTestConfigs()));
} // namespace snapshot
} // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h
index d07d2f8..7c99085 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h
@@ -48,10 +48,27 @@
std::mutex m_lock_;
std::condition_variable m_cv_;
+ /*
+ * Scanning of partitions is an expensive operation both in terms of memory
+ * and CPU usage. The goal here is to scan the partitions fast enough without
+ * significant increase in the boot time.
+ *
+ * Partitions such as system, product which may be huge and may need multiple
+ * threads to speed up the verification process. Using multiple threads for
+ * all partitions may increase CPU usage significantly. Hence, limit that to
+ * 1 thread per partition.
+ *
+ * These numbers were derived by monitoring the memory and CPU pressure
+ * (/proc/pressure/{cpu,memory}; and monitoring the Inactive(file) and
+ * Active(file) pages from /proc/meminfo.
+ *
+ * Additionally, for low memory devices, it is advisible to use O_DIRECT
+ * fucntionality for source block device.
+ */
int kMinThreadsToVerify = 1;
- int kMaxThreadsToVerify = 4;
- uint64_t kThresholdSize = 512_MiB;
- uint64_t kBlockSizeVerify = 1_MiB;
+ int kMaxThreadsToVerify = 3;
+ uint64_t kThresholdSize = 750_MiB;
+ uint64_t kBlockSizeVerify = 2_MiB;
bool IsBlockAligned(uint64_t read_size) { return ((read_size & (BLOCK_SZ - 1)) == 0); }
void UpdatePartitionVerificationState(UpdateVerifyState state);